fix: handle .mp4 as alias for .m4a throughout download pipeline

When an extension's preferred output isn't .m4a, downloaded M4A streams
are now automatically converted to FLAC via FFmpeg instead of being
preserved. This applies to both SAF and non-SAF download paths.

README.md

@@ -168,7 +168,7 @@ Interested in contributing? Check out the [Contributing Guide](CONTRIBUTING.md)
 |---|---|---|---|---|
 | [hifi-api](https://github.com/binimum/hifi-api) | [music.binimum.org](https://music.binimum.org) | [qqdl.site](https://qqdl.site) | [squid.wtf](https://squid.wtf) | [spotisaver.net](https://spotisaver.net) |
 | [dabmusic.xyz](https://dabmusic.xyz) | [AfkarXYZ](https://github.com/afkarxyz) | [LRCLib](https://lrclib.net) | [Paxsenix](https://lyrics.paxsenix.org) | [Cobalt](https://cobalt.tools) |
-| [qwkuns.me](https://qwkuns.me) | [SpotubeDL](https://spotubedl.com) | [Song.link](https://song.link) | [IDHS](https://github.com/sjdonado/idonthavespotify) | |
+| [qwkuns.me](https://qwkuns.me) | [SpotubeDL](https://spotubedl.com) | [Song.link](https://song.link) | [IDHS](https://github.com/sjdonado/idonthavespotify) | [Monochrome](https://monochrome.tf) |
 
 ---
 

android/app/build.gradle.kts

@@ -20,6 +20,10 @@ android {
     compileSdk = flutter.compileSdkVersion
     ndkVersion = flutter.ndkVersion
 
+    buildFeatures {
+        buildConfig = true
+    }
+
     compileOptions {
         isCoreLibraryDesugaringEnabled = true
         sourceCompatibility = JavaVersion.VERSION_17

android/app/src/main/AndroidManifest.xml

@@ -86,6 +86,20 @@
                 <category android:name="android.intent.category.BROWSABLE" />
                 <data android:scheme="https" android:host="music.youtube.com" />
             </intent-filter>
+
+            <!-- Extension OAuth (PKCE) redirect: spotiflac://callback?code=...&state=<extension_id> -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="spotiflac" android:host="callback" />
+            </intent-filter>
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="spotiflac" android:host="spotify-callback" />
+            </intent-filter>
         </activity>
 
         <!-- Download Service -->

android/app/src/main/kotlin/com/zarz/spotiflac/MainActivity.kt

@@ -4,6 +4,7 @@ import android.app.Activity
 import android.content.Intent
 import android.net.Uri
 import android.os.Build
+import android.os.Bundle
 import androidx.activity.OnBackPressedCallback
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.documentfile.provider.DocumentFile
@@ -307,8 +308,40 @@ class MainActivity: FlutterFragmentActivity() {
         }
     }
 
+    private fun forceFilenameExt(name: String, outputExt: String): String {
+        val normalizedExt = normalizeExt(outputExt)
+        if (normalizedExt.isBlank()) return sanitizeFilename(name)
+
+        val safeName = sanitizeFilename(name)
+        val lower = safeName.lowercase(Locale.ROOT)
+        val knownExts = listOf(".flac", ".m4a", ".mp3", ".opus", ".lrc")
+        for (knownExt in knownExts) {
+            if (lower.endsWith(knownExt)) {
+                return safeName.dropLast(knownExt.length) + normalizedExt
+            }
+        }
+        return safeName + normalizedExt
+    }
+
     private fun sanitizeFilename(name: String): String {
-        return name.replace(Regex("[\\\\/:*?\"<>|]"), "_").trim()
+        var sanitized = name
+            .replace("/", " ")
+            .replace(Regex("[\\\\:*?\"<>|]"), " ")
+            .filter { ch ->
+                val code = ch.code
+                !((code < 0x20 && ch != '\t' && ch != '\n' && ch != '\r') ||
+                    code == 0x7F ||
+                    (Character.isISOControl(ch) && ch != '\t' && ch != '\n' && ch != '\r'))
+            }
+            .trim()
+            .trim('.', ' ')
+
+        sanitized = sanitized
+            .replace(Regex("\\s+"), " ")
+            .replace(Regex("_+"), "_")
+            .trim('_', ' ')
+
+        return if (sanitized.isBlank()) "Unknown" else sanitized
     }
 
     private fun sanitizeRelativeDir(relativeDir: String): String {
@@ -368,6 +401,43 @@ class MainActivity: FlutterFragmentActivity() {
         return current
     }
 
+    private fun createOrReuseDocumentFile(
+        parent: DocumentFile,
+        mimeType: String,
+        fileName: String
+    ): DocumentFile? {
+        val safeFileName = sanitizeFilename(fileName)
+        if (safeFileName.isBlank()) return null
+
+        synchronized(safDirLock) {
+            val existing = parent.findFile(safeFileName)
+            if (existing != null && existing.isFile) {
+                return existing
+            }
+
+            val created = parent.createFile(mimeType, safeFileName) ?: return null
+            val createdName = created.name ?: safeFileName
+            if (createdName == safeFileName) {
+                return created
+            }
+
+            // SAF can auto-rename to "name (1)" when another writer wins the race
+            // between findFile() and createFile(). Prefer the exact sibling if it
+            // appeared, and discard the duplicate document we just created.
+            val winner = parent.findFile(safeFileName)
+            if (winner != null && winner.isFile) {
+                if (winner.uri != created.uri) {
+                    try {
+                        created.delete()
+                    } catch (_: Exception) {}
+                }
+                return winner
+            }
+
+            return created
+        }
+    }
+
     private fun resetSafScanProgress() {
         synchronized(safScanLock) {
             safScanProgress = SafScanProgress()
@@ -599,12 +669,12 @@ class MainActivity: FlutterFragmentActivity() {
 
     private fun buildSafFileName(req: JSONObject, outputExt: String): String {
         val provided = req.optString("saf_file_name", "")
-        if (provided.isNotBlank()) return sanitizeFilename(provided)
+        if (provided.isNotBlank()) return forceFilenameExt(provided, outputExt)
 
         val trackName = req.optString("track_name", "track")
         val artistName = req.optString("artist_name", "")
         val baseName = if (artistName.isNotBlank()) "$artistName - $trackName" else trackName
-        return sanitizeFilename(baseName) + outputExt
+        return forceFilenameExt(baseName, outputExt)
     }
 
     private fun errorJson(message: String): String {
@@ -918,8 +988,7 @@ class MainActivity: FlutterFragmentActivity() {
         val targetDir = ensureDocumentDir(treeUri, relativeDir)
             ?: return errorJson("Failed to access SAF directory")
 
-        val existingFile = targetDir.findFile(fileName)
-        val document = existingFile ?: targetDir.createFile(mimeType, fileName)
+        var document = createOrReuseDocumentFile(targetDir, mimeType, fileName)
             ?: return errorJson("Failed to create SAF file")
 
         val pfd = contentResolver.openFileDescriptor(document.uri, "rw")
@@ -947,6 +1016,21 @@ class MainActivity: FlutterFragmentActivity() {
                         if (!srcFile.exists() || srcFile.length() <= 0) {
                             throw IllegalStateException("extension output missing or empty: $goFilePath")
                         }
+                        val actualExt = normalizeExt(srcFile.extension)
+                        if (actualExt.isNotBlank() && actualExt != outputExt) {
+                            val actualFileName = buildSafFileName(req, actualExt)
+                            val actualMimeType = mimeTypeForExt(actualExt)
+                            val replacement = createOrReuseDocumentFile(
+                                targetDir,
+                                actualMimeType,
+                                actualFileName,
+                            )
+                                ?: throw IllegalStateException("failed to create SAF output with actual extension")
+                            if (replacement.uri != document.uri) {
+                                document.delete()
+                                document = replacement
+                            }
+                        }
                         contentResolver.openOutputStream(document.uri, "wt")?.use { output ->
                             srcFile.inputStream().use { input ->
                                 input.copyTo(output)
@@ -1934,9 +2018,54 @@ class MainActivity: FlutterFragmentActivity() {
     // We handle these URLs ourselves via receive_sharing_intent + ShareIntentService.
     override fun shouldHandleDeeplinking(): Boolean = false
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        handleExtensionOAuthIntent(intent)
+    }
+
     override fun onNewIntent(intent: Intent) {
         super.onNewIntent(intent)
         setIntent(intent)
+        handleExtensionOAuthIntent(intent)
+    }
+
+    /**
+     * Deliver Spotify (or other) OAuth authorization code to the extension runtime
+     * and run its token exchange (e.g. completeSpotifyLogin). State must be the extension id.
+     */
+    private fun handleExtensionOAuthIntent(intent: Intent?) {
+        val uri = intent?.data ?: return
+        if (!uri.scheme.equals("spotiflac", ignoreCase = true)) {
+            return
+        }
+        val host = (uri.host ?: "").lowercase(Locale.US)
+        val path = (uri.path ?: "").lowercase(Locale.US)
+        val isCallback =
+            host == "callback" ||
+                host == "spotify-callback" ||
+                path.contains("callback")
+        if (!isCallback) {
+            return
+        }
+        val code = uri.getQueryParameter("code")?.trim().orEmpty()
+        if (code.isEmpty()) {
+            return
+        }
+        val extId = uri.getQueryParameter("state")?.trim().orEmpty()
+        if (extId.isEmpty()) {
+            android.util.Log.w("SpotiFLAC", "Extension OAuth redirect missing state (extension id)")
+            return
+        }
+        intent.data = null
+        scope.launch(Dispatchers.IO) {
+            try {
+                Gobackend.setExtensionAuthCodeByID(extId, code)
+                val json = Gobackend.invokeExtensionActionJSON(extId, "completeSpotifyLogin")
+                android.util.Log.i("SpotiFLAC", "Extension OAuth complete for $extId: $json")
+            } catch (e: Exception) {
+                android.util.Log.w("SpotiFLAC", "Extension OAuth failed: ${e.message}")
+            }
+        }
     }
 
     override fun onDestroy() {
@@ -1952,6 +2081,7 @@ class MainActivity: FlutterFragmentActivity() {
 
     override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
         super.configureFlutterEngine(flutterEngine)
+        Gobackend.setAppVersion(BuildConfig.VERSION_NAME)
 
         // Always-enabled back callback to ensure back presses reach Flutter.
         // Nested tab navigators can incorrectly set frameworkHandlesBack(false),
@@ -2136,7 +2266,6 @@ class MainActivity: FlutterFragmentActivity() {
                                 result.error("saf_pending", "SAF picker already active", null)
                                 return@launch
                             }
-                            pendingSafTreeResult = result
                             val intent = Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
                             intent.addFlags(
                                 Intent.FLAG_GRANT_READ_URI_PERMISSION or
@@ -2144,7 +2273,24 @@ class MainActivity: FlutterFragmentActivity() {
                                     Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION or
                                     Intent.FLAG_GRANT_PREFIX_URI_PERMISSION
                             )
-                            safTreeLauncher.launch(intent)
+                            val resolver = intent.resolveActivity(packageManager)
+                            if (resolver == null) {
+                                result.error("saf_unavailable", "No folder picker available on this device", null)
+                                return@launch
+                            }
+                            pendingSafTreeResult = result
+                            try {
+                                android.util.Log.i("SpotiFLAC", "Launching SAF picker via $resolver")
+                                safTreeLauncher.launch(intent)
+                            } catch (e: Exception) {
+                                pendingSafTreeResult = null
+                                android.util.Log.e("SpotiFLAC", "Failed to launch SAF picker: ${e.message}", e)
+                                result.error(
+                                    "saf_launch_failed",
+                                    e.message ?: "Failed to launch folder picker",
+                                    null
+                                )
+                            }
                         }
                         "safExists" -> {
                             val uriStr = call.argument<String>("uri") ?: ""
@@ -2219,7 +2365,8 @@ class MainActivity: FlutterFragmentActivity() {
                                 val dir = ensureDocumentDir(Uri.parse(treeUriStr), relativeDir) ?: return@withContext null
                                 val existing = dir.findFile(fileName)
                                 val createdNew = existing == null
-                                val doc = existing ?: dir.createFile(mimeType, fileName) ?: return@withContext null
+                                val doc = createOrReuseDocumentFile(dir, mimeType, fileName)
+                                    ?: return@withContext null
                                 if (!writeUriFromPath(doc.uri, srcPath)) {
                                     if (createdNew) {
                                         doc.delete()
@@ -2717,16 +2864,6 @@ class MainActivity: FlutterFragmentActivity() {
                             }
                             result.success(null)
                         }
-                        "searchDeezerAll" -> {
-                            val query = call.argument<String>("query") ?: ""
-                            val trackLimit = call.argument<Int>("track_limit") ?: 15
-                            val artistLimit = call.argument<Int>("artist_limit") ?: 2
-                            val filter = call.argument<String>("filter") ?: ""
-                            val response = withContext(Dispatchers.IO) {
-                                Gobackend.searchDeezerAll(query, trackLimit.toLong(), artistLimit.toLong(), filter)
-                            }
-                            result.success(response)
-                        }
                         "searchTidalAll" -> {
                             val query = call.argument<String>("query") ?: ""
                             val trackLimit = call.argument<Int>("track_limit") ?: 15

android/gradle.properties

@@ -1,2 +1,2 @@
-org.gradle.jvmargs=-Xmx4G -XX:MaxMetaspaceSize=2G -XX:ReservedCodeCacheSize=256m -XX:+HeapDumpOnOutOfMemoryError
+org.gradle.jvmargs=-Xmx2g -XX:MaxMetaspaceSize=512m -XX:ReservedCodeCacheSize=256m -XX:+HeapDumpOnOutOfMemoryError
 android.useAndroidX=true

apps.json

@@ -7,12 +7,12 @@
       "name": "SpotiFLAC",
       "bundleIdentifier": "com.zarzet.spotiflac",
       "developerName": "zarzet",
-      "version": "3.9.0",
-      "versionDate": "2026-03-25",
-      "downloadURL": "https://github.com/zarzet/SpotiFLAC-Mobile/releases/download/v3.9.0/SpotiFLAC-v3.9.0-ios-unsigned.ipa",
+      "version": "4.3.1",
+      "versionDate": "2026-04-14",
+      "downloadURL": "https://github.com/zarzet/SpotiFLAC-Mobile/releases/download/v4.3.1/SpotiFLAC-v4.3.1-ios-unsigned.ipa",
       "localizedDescription": "Mobile version of SpotiFLAC written in Flutter. Download Tracks in true FLAC from Tidal, Qobuz, & Amazon Music.",
       "iconURL": "https://raw.githubusercontent.com/zarzet/SpotiFLAC-Mobile/main/assets/images/logo.png",
-      "size": 34477323
+      "size": 34773598
     }
   ]
 }

go_backend/cancel.go

@@ -10,6 +10,7 @@ import (
 var ErrDownloadCancelled = errors.New("download cancelled")
 
 type cancelEntry struct {
+	ctx      context.Context
 	cancel   context.CancelFunc
 	canceled bool
 }
@@ -27,8 +28,21 @@ func initDownloadCancel(itemID string) context.Context {
 	cancelMu.Lock()
 	defer cancelMu.Unlock()
 
+	if entry, ok := cancelMap[itemID]; ok {
+		if entry.ctx == nil {
+			ctx, cancel := context.WithCancel(context.Background())
+			entry.ctx = ctx
+			entry.cancel = cancel
+			if entry.canceled && entry.cancel != nil {
+				entry.cancel()
+			}
+		}
+		return entry.ctx
+	}
+
 	ctx, cancel := context.WithCancel(context.Background())
 	cancelMap[itemID] = &cancelEntry{
+		ctx:      ctx,
 		cancel:   cancel,
 		canceled: false,
 	}

go_backend/exports.go

@@ -5,12 +5,16 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net/http"
+	"net/url"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
 
 	"github.com/dop251/goja"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 func CheckAvailability(spotifyID, isrc string) (string, error) {
@@ -33,6 +37,113 @@ func SetSongLinkNetworkOptions(allowHTTP, insecureTLS bool) {
 	SetNetworkCompatibilityOptions(allowHTTP, insecureTLS)
 }
 
+const musicBrainzAPIBase = "https://musicbrainz.org/ws/2"
+
+type musicBrainzTag struct {
+	Count int    `json:"count"`
+	Name  string `json:"name"`
+}
+
+type musicBrainzRecordingResponse struct {
+	Recordings []struct {
+		Tags []musicBrainzTag `json:"tags"`
+	} `json:"recordings"`
+}
+
+func formatMusicBrainzGenre(tags []musicBrainzTag) string {
+	if len(tags) == 0 {
+		return ""
+	}
+
+	caser := cases.Title(language.English)
+	seen := make(map[string]struct{}, len(tags))
+	maxCount := -1
+	bestTag := ""
+
+	for _, tag := range tags {
+		name := strings.TrimSpace(tag.Name)
+		if name == "" {
+			continue
+		}
+
+		key := strings.ToLower(name)
+		if _, exists := seen[key]; exists {
+			continue
+		}
+		seen[key] = struct{}{}
+
+		formatted := caser.String(name)
+		if tag.Count > maxCount {
+			maxCount = tag.Count
+			bestTag = formatted
+		}
+	}
+
+	return bestTag
+}
+
+func FetchMusicBrainzGenreByISRC(isrc string) (string, error) {
+	normalizedISRC := strings.ToUpper(strings.TrimSpace(isrc))
+	if normalizedISRC == "" {
+		return "", fmt.Errorf("no ISRC provided")
+	}
+
+	client := NewMetadataHTTPClient(10 * time.Second)
+	query := fmt.Sprintf("isrc:%s", normalizedISRC)
+	reqURL := fmt.Sprintf(
+		"%s/recording?query=%s&fmt=json&inc=tags",
+		musicBrainzAPIBase,
+		url.QueryEscape(query),
+	)
+
+	req, err := http.NewRequest(http.MethodGet, reqURL, nil)
+	if err != nil {
+		return "", err
+	}
+	req.Header.Set("User-Agent", getRandomUserAgent())
+
+	var resp *http.Response
+	var lastErr error
+	for attempt := 0; attempt < 3; attempt++ {
+		resp, lastErr = client.Do(req)
+		if lastErr == nil && resp.StatusCode == http.StatusOK {
+			break
+		}
+		if resp != nil {
+			resp.Body.Close()
+		}
+		if attempt < 2 {
+			time.Sleep(2 * time.Second)
+		}
+	}
+
+	if lastErr != nil {
+		return "", lastErr
+	}
+	if resp == nil {
+		return "", fmt.Errorf("MusicBrainz request failed without response")
+	}
+	if resp.StatusCode != http.StatusOK {
+		resp.Body.Close()
+		return "", fmt.Errorf("MusicBrainz API returned status: %d", resp.StatusCode)
+	}
+	defer resp.Body.Close()
+
+	var payload musicBrainzRecordingResponse
+	if err := json.NewDecoder(resp.Body).Decode(&payload); err != nil {
+		return "", err
+	}
+	if len(payload.Recordings) == 0 {
+		return "", fmt.Errorf("no recordings found for ISRC: %s", normalizedISRC)
+	}
+
+	genre := formatMusicBrainzGenre(payload.Recordings[0].Tags)
+	if genre == "" {
+		return "", fmt.Errorf("no MusicBrainz genre tags found for ISRC: %s", normalizedISRC)
+	}
+	return genre, nil
+}
+
 type DownloadRequest struct {
 	ISRC                 string `json:"isrc"`
 	Service              string `json:"service"`
@@ -127,6 +238,12 @@ type DownloadResult struct {
 	Decryption    *DownloadDecryptionInfo
 }
 
+var fetchDeezerExtendedMetadataByISRC = func(ctx context.Context, isrc string) (*AlbumExtendedMetadata, error) {
+	return GetDeezerClient().GetExtendedMetadataByISRC(ctx, isrc)
+}
+
+var fetchMusicBrainzGenreByISRC = FetchMusicBrainzGenreByISRC
+
 type reEnrichRequest struct {
 	FilePath      string   `json:"file_path"`
 	CoverURL      string   `json:"cover_url"`
@@ -679,6 +796,75 @@ func enrichResultQualityFromFile(result *DownloadResult) {
 	LogDebug("Download", "Post-download quality probe unavailable for %s: %v", path, qErr)
 }
 
+func applyExtendedMetadataFields(
+	genre *string,
+	label *string,
+	copyright *string,
+	extMeta *AlbumExtendedMetadata,
+) {
+	if extMeta == nil {
+		return
+	}
+
+	if genre != nil && *genre == "" && extMeta.Genre != "" {
+		*genre = extMeta.Genre
+	}
+	if label != nil && *label == "" && extMeta.Label != "" {
+		*label = extMeta.Label
+	}
+	if copyright != nil && *copyright == "" && extMeta.Copyright != "" {
+		*copyright = extMeta.Copyright
+	}
+}
+
+func enrichExtraMetadataByISRC(
+	logPrefix string,
+	isrc string,
+	genre *string,
+	label *string,
+	copyright *string,
+) {
+	normalizedISRC := strings.TrimSpace(isrc)
+	if normalizedISRC == "" {
+		return
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	extMeta, err := fetchDeezerExtendedMetadataByISRC(ctx, normalizedISRC)
+	if err != nil {
+		GoLog("[%s] Failed to get extended metadata from Deezer: %v\n", logPrefix, err)
+	}
+	applyExtendedMetadataFields(genre, label, copyright, extMeta)
+
+	if genre != nil && *genre == "" {
+		musicBrainzGenre, err := fetchMusicBrainzGenreByISRC(normalizedISRC)
+		if err != nil {
+			GoLog("[%s] Failed to get genre from MusicBrainz: %v\n", logPrefix, err)
+		} else if musicBrainzGenre != "" {
+			*genre = musicBrainzGenre
+			GoLog("[%s] Genre fallback from MusicBrainz: %s\n", logPrefix, *genre)
+		}
+	}
+
+	currentGenre := ""
+	currentLabel := ""
+	currentCopyright := ""
+	if genre != nil {
+		currentGenre = *genre
+	}
+	if label != nil {
+		currentLabel = *label
+	}
+	if copyright != nil {
+		currentCopyright = *copyright
+	}
+	if currentGenre != "" || currentLabel != "" || currentCopyright != "" {
+		GoLog("[%s] Extended metadata ready: genre=%s, label=%s, copyright=%s\n", logPrefix, currentGenre, currentLabel, currentCopyright)
+	}
+}
+
 func enrichRequestExtendedMetadata(req *DownloadRequest) {
 	if req == nil {
 		return
@@ -688,30 +874,13 @@ func enrichRequestExtendedMetadata(req *DownloadRequest) {
 		return
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-
-	deezerClient := GetDeezerClient()
-	extMeta, err := deezerClient.GetExtendedMetadataByISRC(ctx, req.ISRC)
-	if err != nil || extMeta == nil {
-		if err != nil {
-			GoLog("[DownloadWithFallback] Failed to get extended metadata from Deezer: %v\n", err)
-		}
-		return
-	}
-
-	if req.Genre == "" && extMeta.Genre != "" {
-		req.Genre = extMeta.Genre
-	}
-	if req.Label == "" && extMeta.Label != "" {
-		req.Label = extMeta.Label
-	}
-	if req.Copyright == "" && extMeta.Copyright != "" {
-		req.Copyright = extMeta.Copyright
-	}
-	if req.Genre != "" || req.Label != "" || req.Copyright != "" {
-		GoLog("[DownloadWithFallback] Extended metadata ready: genre=%s, label=%s, copyright=%s\n", req.Genre, req.Label, req.Copyright)
-	}
+	enrichExtraMetadataByISRC(
+		"DownloadWithFallback",
+		req.ISRC,
+		&req.Genre,
+		&req.Label,
+		&req.Copyright,
+	)
 }
 
 func applySongLinkRegionFromRequest(req *DownloadRequest) {
@@ -1316,6 +1485,7 @@ func EditFileMetadata(filePath, metadataJSON string) (string, error) {
 	lower := strings.ToLower(filePath)
 	isFlac := strings.HasSuffix(lower, ".flac")
 	isApeFile := strings.HasSuffix(lower, ".ape") || strings.HasSuffix(lower, ".wv") || strings.HasSuffix(lower, ".mpc")
+	isM4AFile := strings.HasSuffix(lower, ".m4a") || strings.HasSuffix(lower, ".mp4") || strings.HasSuffix(lower, ".m4b")
 	coverPath := strings.TrimSpace(fields["cover_path"])
 
 	if isFlac {
@@ -1361,6 +1531,7 @@ func EditFileMetadata(filePath, metadataJSON string) (string, error) {
 			DiscNumber:          discNum,
 			TotalDiscs:          totalDiscs,
 			ISRC:                fields["isrc"],
+			Lyrics:              fields["lyrics"],
 			Genre:               fields["genre"],
 			Label:               fields["label"],
 			Copyright:           fields["copyright"],
@@ -1427,6 +1598,19 @@ func EditFileMetadata(filePath, metadataJSON string) (string, error) {
 		return string(jsonBytes), nil
 	}
 
+	if isM4AFile && hasOnlyM4AReplayGainFields(fields) {
+		if err := EditM4AReplayGain(filePath, fields); err != nil {
+			return "", fmt.Errorf("failed to write M4A metadata: %w", err)
+		}
+
+		resp := map[string]any{
+			"success": true,
+			"method":  "native_m4a_replaygain",
+		}
+		jsonBytes, _ := json.Marshal(resp)
+		return string(jsonBytes), nil
+	}
+
 	resp := map[string]any{
 		"success": true,
 		"method":  "ffmpeg",
@@ -1436,6 +1620,29 @@ func EditFileMetadata(filePath, metadataJSON string) (string, error) {
 	return string(jsonBytes), nil
 }
 
+func hasOnlyM4AReplayGainFields(fields map[string]string) bool {
+	allowed := map[string]struct{}{
+		"replaygain_track_gain": {},
+		"replaygain_track_peak": {},
+		"replaygain_album_gain": {},
+		"replaygain_album_peak": {},
+	}
+
+	hasReplayGain := false
+	for key, value := range fields {
+		if strings.TrimSpace(value) == "" {
+			continue
+		}
+		if _, ok := allowed[strings.ToLower(strings.TrimSpace(key))]; ok {
+			hasReplayGain = true
+			continue
+		}
+		return false
+	}
+
+	return hasReplayGain
+}
+
 func SetDownloadDirectory(path string) error {
 	return setDownloadDir(path)
 }
@@ -1672,24 +1879,6 @@ func ClearTrackIDCache() {
 	ClearTrackCache()
 }
 
-func SearchDeezerAll(query string, trackLimit, artistLimit int, filter string) (string, error) {
-	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
-	defer cancel()
-
-	client := GetDeezerClient()
-	results, err := client.SearchAll(ctx, query, trackLimit, artistLimit, filter)
-	if err != nil {
-		return "", err
-	}
-
-	jsonBytes, err := json.Marshal(results)
-	if err != nil {
-		return "", err
-	}
-
-	return string(jsonBytes), nil
-}
-
 func SearchTidalAll(query string, trackLimit, artistLimit int, filter string) (string, error) {
 	downloader := NewTidalDownloader()
 	results, err := downloader.SearchAll(query, trackLimit, artistLimit, filter)
@@ -2298,7 +2487,6 @@ func ReEnrichFile(requestJSON string) (string, error) {
 	if req.SearchOnline {
 		found := false
 
-		deezerClient := GetDeezerClient()
 		GoLog("[ReEnrich] Trying metadata providers in configured priority...\n")
 		manager := getExtensionManager()
 		if identifierTrack, err := resolveReEnrichTrackFromIdentifiers(req); err == nil && identifierTrack != nil {
@@ -2327,23 +2515,9 @@ func ReEnrichFile(requestJSON string) (string, error) {
 			GoLog("[ReEnrich] Skipping provider search: no usable title/artist/album query\n")
 		}
 
-		// Try to get extended metadata from Deezer if not already set
+		// Try to enrich extra metadata from ISRC if not already set.
 		if found && req.ISRC != "" && req.shouldUpdateField("extra") && (req.Genre == "" || req.Label == "" || req.Copyright == "") {
-			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-			extMeta, err := deezerClient.GetExtendedMetadataByISRC(ctx, req.ISRC)
-			cancel()
-			if err == nil && extMeta != nil {
-				if req.Genre == "" && extMeta.Genre != "" {
-					req.Genre = extMeta.Genre
-				}
-				if req.Label == "" && extMeta.Label != "" {
-					req.Label = extMeta.Label
-				}
-				if req.Copyright == "" && extMeta.Copyright != "" {
-					req.Copyright = extMeta.Copyright
-				}
-				GoLog("[ReEnrich] Extended metadata: genre=%s, label=%s, copyright=%s\n", req.Genre, req.Label, req.Copyright)
-			}
+			enrichExtraMetadataByISRC("ReEnrich", req.ISRC, &req.Genre, &req.Label, &req.Copyright)
 		}
 
 		if !found {

go_backend/exports_test.go

@@ -1,6 +1,9 @@
 package gobackend
 
-import "testing"
+import (
+	"context"
+	"testing"
+)
 
 func TestSetExtensionFallbackProviderIDsJSONEmptyStringResetsDefault(t *testing.T) {
 	original := GetExtensionFallbackProviderIDs()
@@ -161,6 +164,92 @@ func TestBuildDownloadSuccessResponseNormalizesDecryptionDescriptor(t *testing.T
 	}
 }
 
+func TestFormatMusicBrainzGenrePrefersHighestCountTag(t *testing.T) {
+	got := formatMusicBrainzGenre([]musicBrainzTag{
+		{Name: "art pop", Count: 3},
+		{Name: "pop", Count: 8},
+		{Name: "dance pop", Count: 5},
+	})
+
+	if got != "Pop" {
+		t.Fatalf("genre = %q, want %q", got, "Pop")
+	}
+}
+
+func TestEnrichExtraMetadataByISRCFallsBackToMusicBrainzGenre(t *testing.T) {
+	origDeezerFetcher := fetchDeezerExtendedMetadataByISRC
+	origMusicBrainzFetcher := fetchMusicBrainzGenreByISRC
+	defer func() {
+		fetchDeezerExtendedMetadataByISRC = origDeezerFetcher
+		fetchMusicBrainzGenreByISRC = origMusicBrainzFetcher
+	}()
+
+	fetchDeezerExtendedMetadataByISRC = func(ctx context.Context, isrc string) (*AlbumExtendedMetadata, error) {
+		return nil, nil
+	}
+	fetchMusicBrainzGenreByISRC = func(isrc string) (string, error) {
+		if isrc != "TEST123" {
+			t.Fatalf("unexpected isrc: %q", isrc)
+		}
+		return "Alternative Rock", nil
+	}
+
+	genre := ""
+	label := ""
+	copyright := ""
+	enrichExtraMetadataByISRC("DownloadWithFallback", "TEST123", &genre, &label, &copyright)
+
+	if genre != "Alternative Rock" {
+		t.Fatalf("genre = %q, want fallback genre", genre)
+	}
+	if label != "" {
+		t.Fatalf("label = %q, want empty", label)
+	}
+	if copyright != "" {
+		t.Fatalf("copyright = %q, want empty", copyright)
+	}
+}
+
+func TestEnrichExtraMetadataByISRCPrefersDeezerGenre(t *testing.T) {
+	origDeezerFetcher := fetchDeezerExtendedMetadataByISRC
+	origMusicBrainzFetcher := fetchMusicBrainzGenreByISRC
+	defer func() {
+		fetchDeezerExtendedMetadataByISRC = origDeezerFetcher
+		fetchMusicBrainzGenreByISRC = origMusicBrainzFetcher
+	}()
+
+	musicBrainzCalled := false
+	fetchDeezerExtendedMetadataByISRC = func(ctx context.Context, isrc string) (*AlbumExtendedMetadata, error) {
+		return &AlbumExtendedMetadata{
+			Genre:     "Synthpop",
+			Label:     "EMI",
+			Copyright: "(C) Test",
+		}, nil
+	}
+	fetchMusicBrainzGenreByISRC = func(isrc string) (string, error) {
+		musicBrainzCalled = true
+		return "Rock", nil
+	}
+
+	genre := ""
+	label := ""
+	copyright := ""
+	enrichExtraMetadataByISRC("DownloadWithFallback", "TEST456", &genre, &label, &copyright)
+
+	if genre != "Synthpop" {
+		t.Fatalf("genre = %q, want Deezer genre", genre)
+	}
+	if label != "EMI" {
+		t.Fatalf("label = %q, want Deezer label", label)
+	}
+	if copyright != "(C) Test" {
+		t.Fatalf("copyright = %q, want Deezer copyright", copyright)
+	}
+	if musicBrainzCalled {
+		t.Fatal("expected MusicBrainz not to be called when Deezer already provides genre")
+	}
+}
+
 func TestApplyReEnrichTrackMetadataPreservesExistingReleaseDateWhenCandidateMissing(t *testing.T) {
 	req := reEnrichRequest{
 		SpotifyID:   "spotify-track-id",

go_backend/extension_manager.go

@@ -893,7 +893,6 @@ func (m *extensionManager) GetInstalledExtensionsJSON() (string, error) {
 		Name                   string                 `json:"name"`
 		DisplayName            string                 `json:"display_name"`
 		Version                string                 `json:"version"`
-		Author                 string                 `json:"author"`
 		Description            string                 `json:"description"`
 		Homepage               string                 `json:"homepage,omitempty"`
 		IconPath               string                 `json:"icon_path,omitempty"`
@@ -951,7 +950,6 @@ func (m *extensionManager) GetInstalledExtensionsJSON() (string, error) {
 			Name:                   ext.Manifest.Name,
 			DisplayName:            ext.Manifest.DisplayName,
 			Version:                ext.Manifest.Version,
-			Author:                 ext.Manifest.Author,
 			Description:            ext.Manifest.Description,
 			Homepage:               ext.Manifest.Homepage,
 			IconPath:               iconPath,
@@ -1055,15 +1053,29 @@ func (m *extensionManager) InvokeAction(extensionID string, actionName string) (
 	}
 	defer ext.VMMu.Unlock()
 
+	// Merge extension return values onto the top-level JSON object so Flutter can read
+	// message, open_auth_url, setting_updates without unwrapping a nested "result" key.
 	script := fmt.Sprintf(`
 		(function() {
 			if (typeof extension !== 'undefined' && typeof extension.%s === 'function') {
 				try {
 					var result = extension.%s();
 					if (result && typeof result.then === 'function') {
-						// Handle promise - return pending status
 						return { success: true, pending: true, message: 'Action started' };
 					}
+					if (result !== null && result !== undefined && typeof result === 'object') {
+						var isArr = false;
+						if (typeof Array !== 'undefined' && Array.isArray) {
+							isArr = Array.isArray(result);
+						}
+						if (!isArr) {
+							var out = { success: true };
+							for (var k in result) {
+								out[k] = result[k];
+							}
+							return out;
+						}
+					}
 					return { success: true, result: result };
 				} catch (e) {
 					return { success: false, error: e.toString() };

go_backend/extension_manifest.go

@@ -105,7 +105,6 @@ type ExtensionManifest struct {
 	Name                   string                 `json:"name"`
 	DisplayName            string                 `json:"displayName"`
 	Version                string                 `json:"version"`
-	Author                 string                 `json:"author"`
 	Description            string                 `json:"description"`
 	Homepage               string                 `json:"homepage,omitempty"`
 	Icon                   string                 `json:"icon,omitempty"`
@@ -155,10 +154,6 @@ func (m *ExtensionManifest) Validate() error {
 		return &ManifestValidationError{Field: "version", Message: "version is required"}
 	}
 
-	if strings.TrimSpace(m.Author) == "" {
-		return &ManifestValidationError{Field: "author", Message: "author is required"}
-	}
-
 	if strings.TrimSpace(m.Description) == "" {
 		return &ManifestValidationError{Field: "description", Message: "description is required"}
 	}

go_backend/extension_providers.go

@@ -1,7 +1,6 @@
 package gobackend
 
 import (
-	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -119,9 +118,16 @@ type ExtDownloadResult struct {
 	AlbumArtist   string                  `json:"album_artist,omitempty"`
 	TrackNumber   int                     `json:"track_number,omitempty"`
 	DiscNumber    int                     `json:"disc_number,omitempty"`
+	TotalTracks   int                     `json:"total_tracks,omitempty"`
+	TotalDiscs    int                     `json:"total_discs,omitempty"`
 	ReleaseDate   string                  `json:"release_date,omitempty"`
 	CoverURL      string                  `json:"cover_url,omitempty"`
 	ISRC          string                  `json:"isrc,omitempty"`
+	Genre         string                  `json:"genre,omitempty"`
+	Label         string                  `json:"label,omitempty"`
+	Copyright     string                  `json:"copyright,omitempty"`
+	Composer      string                  `json:"composer,omitempty"`
+	LyricsLRC     string                  `json:"lyrics_lrc,omitempty"`
 	DecryptionKey string                  `json:"decryption_key,omitempty"`
 	Decryption    *DownloadDecryptionInfo `json:"decryption,omitempty"`
 }
@@ -616,6 +622,10 @@ func (p *extensionProviderWrapper) Download(trackID, quality, outputPath, itemID
 		p.extension.runtime.setActiveDownloadItemID(itemID)
 		defer p.extension.runtime.clearActiveDownloadItemID()
 	}
+	if itemID != "" {
+		initDownloadCancel(itemID)
+		defer clearDownloadCancel(itemID)
+	}
 
 	p.vm.Set("__onProgress", func(call goja.FunctionCall) goja.Value {
 		if len(call.Arguments) > 0 {
@@ -806,9 +816,6 @@ func sanitizeDownloadProviderPriority(providerIDs []string) []string {
 		}
 
 		normalizedBuiltIn := strings.ToLower(providerID)
-		if normalizedBuiltIn == "deezer" {
-			continue
-		}
 		if isBuiltInDownloadProvider(normalizedBuiltIn) {
 			providerID = normalizedBuiltIn
 		}
@@ -895,7 +902,7 @@ func SetMetadataProviderPriority(providerIDs []string) {
 	metadataProviderPriorityMu.Lock()
 	defer metadataProviderPriorityMu.Unlock()
 
-	sanitized := make([]string, 0, len(providerIDs)+3)
+	sanitized := make([]string, 0, len(providerIDs)+2)
 	seen := map[string]struct{}{}
 	for _, providerID := range providerIDs {
 		providerID = strings.TrimSpace(providerID)
@@ -908,7 +915,7 @@ func SetMetadataProviderPriority(providerIDs []string) {
 		seen[providerID] = struct{}{}
 		sanitized = append(sanitized, providerID)
 	}
-	for _, providerID := range []string{"deezer", "qobuz", "tidal"} {
+	for _, providerID := range []string{"qobuz", "tidal"} {
 		if _, exists := seen[providerID]; exists {
 			continue
 		}
@@ -925,7 +932,7 @@ func GetMetadataProviderPriority() []string {
 	defer metadataProviderPriorityMu.RUnlock()
 
 	if len(metadataProviderPriority) == 0 {
-		return []string{"deezer", "qobuz", "tidal"}
+		return []string{"qobuz", "tidal"}
 	}
 
 	result := make([]string, len(metadataProviderPriority))
@@ -935,7 +942,7 @@ func GetMetadataProviderPriority() []string {
 
 func isBuiltInProvider(providerID string) bool {
 	switch providerID {
-	case "tidal", "qobuz", "deezer":
+	case "tidal", "qobuz":
 		return true
 	default:
 		return false
@@ -951,6 +958,19 @@ func isBuiltInDownloadProvider(providerID string) bool {
 	}
 }
 
+func normalizeQualityForBuiltIn(quality string) string {
+	switch strings.ToLower(strings.TrimSpace(quality)) {
+	case "alac", "hi_res_lossless", "lossless":
+		return "HI_RES_LOSSLESS"
+	case "atmos", "ac3", "dolby_atmos":
+		return "LOSSLESS"
+	case "aac", "aac-legacy":
+		return "LOSSLESS"
+	default:
+		return quality
+	}
+}
+
 func normalizeBuiltInMetadataTrack(track TrackMetadata, providerID string) ExtTrackMetadata {
 	deezerID := ""
 	tidalID := ""
@@ -1006,20 +1026,6 @@ func metadataTrackDedupKey(track ExtTrackMetadata) string {
 
 func searchBuiltInMetadataTracks(providerID, query string, limit int) ([]ExtTrackMetadata, error) {
 	switch providerID {
-	case "deezer":
-		ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
-		defer cancel()
-
-		results, err := GetDeezerClient().SearchAll(ctx, query, limit, 0, "track")
-		if err != nil {
-			return nil, err
-		}
-
-		tracks := make([]ExtTrackMetadata, 0, len(results.Tracks))
-		for _, track := range results.Tracks {
-			tracks = append(tracks, normalizeBuiltInMetadataTrack(track, "deezer"))
-		}
-		return tracks, nil
 	case "qobuz":
 		return NewQobuzDownloader().SearchTracks(query, limit)
 	case "tidal":
@@ -1327,28 +1333,14 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 
 		if req.ISRC != "" &&
 			(req.Genre == "" || req.Label == "" || req.Copyright == "") {
-			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-			extMeta, err := GetDeezerClient().GetExtendedMetadataByISRC(ctx, req.ISRC)
-			cancel()
-			if err == nil && extMeta != nil {
-				if req.Genre == "" && extMeta.Genre != "" {
-					req.Genre = extMeta.Genre
-				}
-				if req.Label == "" && extMeta.Label != "" {
-					req.Label = extMeta.Label
-				}
-				if req.Copyright == "" && extMeta.Copyright != "" {
-					req.Copyright = extMeta.Copyright
-				}
-				GoLog("[DownloadWithExtensionFallback] Extended metadata from Deezer: genre=%s, label=%s, copyright=%s\n", req.Genre, req.Label, req.Copyright)
-			}
+			enrichExtraMetadataByISRC("DownloadWithExtensionFallback", req.ISRC, &req.Genre, &req.Label, &req.Copyright)
 		}
 	}
 
 	if req.Source != "" &&
 		!isBuiltInProvider(strings.ToLower(req.Source)) &&
-		(!strictMode || selectedProvider == "" || strings.EqualFold(selectedProvider, req.Source)) {
-		GoLog("[DownloadWithExtensionFallback] Track source is extension '%s', trying it first\n", req.Source)
+		selectedProvider == req.Source {
+		GoLog("[DownloadWithExtensionFallback] Track source is extension '%s' matching selected provider, trying it first\n", req.Source)
 
 		ext, err := extManager.GetExtension(req.Source)
 		if err == nil && ext.Enabled && ext.Error == "" && ext.Manifest.IsDownloadProvider() {
@@ -1430,6 +1422,12 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					if result.DiscNumber > 0 {
 						resp.DiscNumber = result.DiscNumber
 					}
+					if result.TotalTracks > 0 {
+						resp.TotalTracks = result.TotalTracks
+					}
+					if result.TotalDiscs > 0 {
+						resp.TotalDiscs = result.TotalDiscs
+					}
 					if result.ReleaseDate != "" {
 						resp.ReleaseDate = result.ReleaseDate
 					}
@@ -1439,8 +1437,29 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					if result.ISRC != "" {
 						resp.ISRC = result.ISRC
 					}
+					if result.Genre != "" {
+						resp.Genre = result.Genre
+					}
+					if result.Label != "" {
+						resp.Label = result.Label
+					}
+					if result.Copyright != "" {
+						resp.Copyright = result.Copyright
+					}
+					if result.Composer != "" {
+						resp.Composer = result.Composer
+					}
+					if result.LyricsLRC != "" {
+						resp.LyricsLRC = result.LyricsLRC
+					}
 				}
 
+				if req.TrackName != "" && resp.Title == "" {
+					resp.Title = req.TrackName
+				}
+				if req.ArtistName != "" && resp.Artist == "" {
+					resp.Artist = req.ArtistName
+				}
 				if req.AlbumName != "" && resp.Album == "" {
 					resp.Album = req.AlbumName
 				}
@@ -1459,9 +1478,18 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 				if req.DiscNumber > 0 && resp.DiscNumber == 0 {
 					resp.DiscNumber = req.DiscNumber
 				}
+				if req.TotalTracks > 0 && resp.TotalTracks == 0 {
+					resp.TotalTracks = req.TotalTracks
+				}
+				if req.TotalDiscs > 0 && resp.TotalDiscs == 0 {
+					resp.TotalDiscs = req.TotalDiscs
+				}
 				if req.CoverURL != "" && resp.CoverURL == "" {
 					resp.CoverURL = req.CoverURL
 				}
+				if req.Composer != "" && resp.Composer == "" {
+					resp.Composer = req.Composer
+				}
 
 				return resp, nil
 			}
@@ -1518,32 +1546,17 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 		GoLog("[DownloadWithExtensionFallback] Trying provider: %s\n", providerID)
 
 		if isBuiltInDownloadProvider(providerIDNormalized) {
+			req.OutputExt = ""
 			if (req.Genre == "" || req.Label == "" || req.Copyright == "") &&
 				req.ISRC != "" {
-				GoLog("[DownloadWithExtensionFallback] Enriching extended metadata from Deezer for ISRC: %s\n", req.ISRC)
-				ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-				deezerClient := GetDeezerClient()
-				extMeta, err := deezerClient.GetExtendedMetadataByISRC(ctx, req.ISRC)
-				cancel()
-				if err == nil && extMeta != nil {
-					if req.Genre == "" && extMeta.Genre != "" {
-						req.Genre = extMeta.Genre
-						GoLog("[DownloadWithExtensionFallback] Genre from Deezer: %s\n", req.Genre)
-					}
-					if req.Label == "" && extMeta.Label != "" {
-						req.Label = extMeta.Label
-						GoLog("[DownloadWithExtensionFallback] Label from Deezer: %s\n", req.Label)
-					}
-					if req.Copyright == "" && extMeta.Copyright != "" {
-						req.Copyright = extMeta.Copyright
-						GoLog("[DownloadWithExtensionFallback] Copyright from Deezer: %s\n", req.Copyright)
-					}
-				} else if err != nil {
-					GoLog("[DownloadWithExtensionFallback] Failed to get extended metadata from Deezer: %v\n", err)
-				}
+				GoLog("[DownloadWithExtensionFallback] Enriching extra metadata from ISRC: %s\n", req.ISRC)
+				enrichExtraMetadataByISRC("DownloadWithExtensionFallback", req.ISRC, &req.Genre, &req.Label, &req.Copyright)
 			}
 
+			origQuality := req.Quality
+			req.Quality = normalizeQualityForBuiltIn(req.Quality)
 			result, err := tryBuiltInProvider(providerIDNormalized, req)
+			req.Quality = origQuality
 			if err == nil && result.Success {
 				result.Service = providerIDNormalized
 				if req.Label != "" {
@@ -1594,6 +1607,7 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 				continue
 			}
 
+			req.OutputExt = ""
 			outputPath := buildOutputPathForExtension(req, ext)
 			if req.ItemID != "" {
 				StartItemProgress(req.ItemID)
@@ -1906,6 +1920,9 @@ func canEmbedGenreLabel(filePath string) bool {
 	if path == "" || strings.HasPrefix(path, "content://") || strings.HasPrefix(path, "/proc/self/fd/") {
 		return false
 	}
+	if strings.ToLower(filepath.Ext(path)) != ".flac" {
+		return false
+	}
 	if !filepath.IsAbs(path) {
 		return false
 	}

go_backend/extension_providers_test.go

@@ -12,7 +12,7 @@ func TestSetMetadataProviderPriorityAddsBuiltIns(t *testing.T) {
 
 	SetMetadataProviderPriority([]string{"tidal"})
 	got := GetMetadataProviderPriority()
-	want := []string{"tidal", "deezer", "qobuz"}
+	want := []string{"tidal", "qobuz"}
 	if len(got) != len(want) {
 		t.Fatalf("unexpected priority length: got %v want %v", got, want)
 	}
@@ -185,6 +185,10 @@ func TestCanEmbedGenreLabelRequiresExistingAbsoluteLocalFile(t *testing.T) {
 	if err := os.WriteFile(tempFile, []byte("fLaC"), 0644); err != nil {
 		t.Fatalf("failed to create temp file: %v", err)
 	}
+	tempM4A := filepath.Join(t.TempDir(), "track.m4a")
+	if err := os.WriteFile(tempM4A, []byte("not-flac"), 0644); err != nil {
+		t.Fatalf("failed to create temp m4a file: %v", err)
+	}
 
 	if canEmbedGenreLabel("relative.flac") {
 		t.Fatal("expected relative path to be rejected")
@@ -195,6 +199,9 @@ func TestCanEmbedGenreLabelRequiresExistingAbsoluteLocalFile(t *testing.T) {
 	if canEmbedGenreLabel(filepath.Join(t.TempDir(), "missing.flac")) {
 		t.Fatal("expected missing file to be rejected")
 	}
+	if canEmbedGenreLabel(tempM4A) {
+		t.Fatalf("expected non-FLAC file %q to be rejected", tempM4A)
+	}
 	if !canEmbedGenreLabel(tempFile) {
 		t.Fatalf("expected existing absolute file %q to be accepted", tempFile)
 	}
@@ -208,7 +215,7 @@ func TestSearchTracksWithMetadataProvidersUsesPriorityAndDedupes(t *testing.T) {
 		searchBuiltInMetadataTracksFunc = originalSearch
 	}()
 
-	SetMetadataProviderPriority([]string{"qobuz", "tidal", "deezer"})
+	SetMetadataProviderPriority([]string{"qobuz", "tidal"})
 
 	var calls []string
 	searchBuiltInMetadataTracksFunc = func(providerID, query string, limit int) ([]ExtTrackMetadata, error) {
@@ -223,10 +230,6 @@ func TestSearchTracksWithMetadataProvidersUsesPriorityAndDedupes(t *testing.T) {
 				{ProviderID: "tidal", SpotifyID: "tidal:2", ISRC: "AAA111", Name: "Duplicate"},
 				{ProviderID: "tidal", SpotifyID: "tidal:3", ISRC: "BBB222", Name: "Second"},
 			}, nil
-		case "deezer":
-			return []ExtTrackMetadata{
-				{ProviderID: "deezer", SpotifyID: "deezer:4", ISRC: "CCC333", Name: "Third"},
-			}, nil
 		default:
 			return nil, nil
 		}
@@ -237,13 +240,13 @@ func TestSearchTracksWithMetadataProvidersUsesPriorityAndDedupes(t *testing.T) {
 	if err != nil {
 		t.Fatalf("SearchTracksWithMetadataProviders returned error: %v", err)
 	}
-	if len(tracks) != 3 {
-		t.Fatalf("unexpected track count: got %d want 3", len(tracks))
+	if len(tracks) != 2 {
+		t.Fatalf("unexpected track count: got %d want 2", len(tracks))
 	}
-	if tracks[0].ProviderID != "qobuz" || tracks[1].ProviderID != "tidal" || tracks[2].ProviderID != "deezer" {
+	if tracks[0].ProviderID != "qobuz" || tracks[1].ProviderID != "tidal" {
 		t.Fatalf("unexpected track provider order: %+v", tracks)
 	}
-	if len(calls) != 3 || calls[0] != "qobuz" || calls[1] != "tidal" || calls[2] != "deezer" {
+	if len(calls) != 2 || calls[0] != "qobuz" || calls[1] != "tidal" {
 		t.Fatalf("unexpected provider call order: %v", calls)
 	}
 }

go_backend/extension_runtime.go

@@ -5,6 +5,7 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -136,12 +137,60 @@ func newExtensionRuntime(ext *loadedExtension) *extensionRuntime {
 		storageFlushDelay: defaultStorageFlushDelay,
 	}
 
-	runtime.httpClient = newExtensionHTTPClient(ext, jar, 30*time.Second)
+	runtime.httpClient = newExtensionHTTPClient(ext, jar, extensionHTTPTimeout(ext, 30*time.Second))
 	runtime.downloadClient = newExtensionHTTPClient(ext, jar, DownloadTimeout)
 
 	return runtime
 }
 
+func extensionHTTPTimeout(ext *loadedExtension, fallback time.Duration) time.Duration {
+	if ext == nil || ext.Manifest == nil || ext.Manifest.Capabilities == nil {
+		return fallback
+	}
+
+	raw, ok := ext.Manifest.Capabilities["networkTimeoutSeconds"]
+	if !ok {
+		return fallback
+	}
+
+	seconds := parseExtensionTimeoutSeconds(raw)
+	if seconds <= 0 {
+		return fallback
+	}
+
+	if seconds < 5 {
+		seconds = 5
+	}
+	if seconds > 300 {
+		seconds = 300
+	}
+
+	return time.Duration(seconds) * time.Second
+}
+
+func parseExtensionTimeoutSeconds(raw interface{}) int {
+	switch v := raw.(type) {
+	case int:
+		return v
+	case int32:
+		return int(v)
+	case int64:
+		return int(v)
+	case float32:
+		return int(v)
+	case float64:
+		return int(v)
+	case string:
+		parsed, err := strconv.Atoi(strings.TrimSpace(v))
+		if err != nil {
+			return 0
+		}
+		return parsed
+	default:
+		return 0
+	}
+}
+
 func (r *extensionRuntime) setActiveDownloadItemID(itemID string) {
 	r.activeDownloadMu.Lock()
 	defer r.activeDownloadMu.Unlock()
@@ -160,6 +209,19 @@ func (r *extensionRuntime) getActiveDownloadItemID() string {
 	return r.activeDownloadItemID
 }
 
+func (r *extensionRuntime) bindDownloadCancelContext(req *http.Request) *http.Request {
+	if req == nil {
+		return nil
+	}
+
+	itemID := r.getActiveDownloadItemID()
+	if itemID == "" {
+		return req
+	}
+
+	return req.WithContext(initDownloadCancel(itemID))
+}
+
 func newExtensionHTTPClient(ext *loadedExtension, jar http.CookieJar, timeout time.Duration) *http.Client {
 	// Extension sandbox enforces HTTPS-only domains. Do not apply global
 	// allow_http scheme downgrade here, because some extension APIs (e.g.
@@ -413,6 +475,10 @@ func (r *extensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	utilsObj.Set("decryptBlockCipher", r.decryptBlockCipher)
 	utilsObj.Set("generateKey", r.cryptoGenerateKey)
 	utilsObj.Set("randomUserAgent", r.randomUserAgent)
+	utilsObj.Set("appVersion", r.appVersion)
+	utilsObj.Set("appUserAgent", r.appUserAgent)
+	utilsObj.Set("sleep", r.sleep)
+	utilsObj.Set("isDownloadCancelled", r.isDownloadCancelled)
 	vm.Set("utils", utilsObj)
 
 	logObj := vm.NewObject()

go_backend/extension_runtime_auth.go

@@ -458,6 +458,7 @@ func (r *extensionRuntime) authExchangeCodeWithPKCE(call goja.FunctionCall) goja
 			"error":   err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 	req.Header.Set("User-Agent", "SpotiFLAC-Extension/1.0")

go_backend/extension_runtime_file.go

@@ -166,6 +166,7 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 			"error":   err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)

go_backend/extension_runtime_http.go

@@ -81,6 +81,7 @@ func (r *extensionRuntime) httpGet(call goja.FunctionCall) goja.Value {
 			"error": err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)
@@ -175,6 +176,7 @@ func (r *extensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 			"error": err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)
@@ -284,6 +286,7 @@ func (r *extensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 			"error": err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)
@@ -410,6 +413,7 @@ func (r *extensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 			"error": err.Error(),
 		})
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)

go_backend/extension_runtime_polyfills.go

@@ -69,6 +69,7 @@ func (r *extensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 	if err != nil {
 		return r.createFetchError(err.Error())
 	}
+	req = r.bindDownloadCancelContext(req)
 
 	for k, v := range headers {
 		req.Header.Set(k, v)

go_backend/extension_runtime_utils.go

@@ -249,6 +249,69 @@ func (r *extensionRuntime) randomUserAgent(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(getRandomUserAgent())
 }
 
+func (r *extensionRuntime) appVersion(call goja.FunctionCall) goja.Value {
+	return r.vm.ToValue(GetAppVersion())
+}
+
+func (r *extensionRuntime) appUserAgent(call goja.FunctionCall) goja.Value {
+	return r.vm.ToValue(appUserAgent())
+}
+
+func (r *extensionRuntime) sleep(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(true)
+	}
+
+	sleepMs := 0
+	switch value := call.Arguments[0].Export().(type) {
+	case int64:
+		sleepMs = int(value)
+	case int32:
+		sleepMs = int(value)
+	case int:
+		sleepMs = value
+	case float64:
+		sleepMs = int(value)
+	default:
+		sleepMs = 0
+	}
+
+	if sleepMs <= 0 {
+		return r.vm.ToValue(true)
+	}
+	if sleepMs > 5*60*1000 {
+		sleepMs = 5 * 60 * 1000
+	}
+
+	itemID := r.getActiveDownloadItemID()
+	deadline := time.Now().Add(time.Duration(sleepMs) * time.Millisecond)
+
+	for {
+		if itemID != "" && isDownloadCancelled(itemID) {
+			return r.vm.ToValue(false)
+		}
+
+		remaining := time.Until(deadline)
+		if remaining <= 0 {
+			return r.vm.ToValue(true)
+		}
+
+		step := 100 * time.Millisecond
+		if remaining < step {
+			step = remaining
+		}
+		time.Sleep(step)
+	}
+}
+
+func (r *extensionRuntime) isDownloadCancelled(call goja.FunctionCall) goja.Value {
+	itemID := r.getActiveDownloadItemID()
+	if itemID == "" {
+		return r.vm.ToValue(false)
+	}
+	return r.vm.ToValue(isDownloadCancelled(itemID))
+}
+
 func (r *extensionRuntime) logDebug(call goja.FunctionCall) goja.Value {
 	msg := r.formatLogArgs(call.Arguments)
 	GoLog("[Extension:%s:DEBUG] %s\n", r.extensionID, msg)

go_backend/extension_store.go

@@ -26,7 +26,6 @@ type storeExtension struct {
 	Name             string   `json:"name"`
 	DisplayName      string   `json:"display_name,omitempty"`
 	Version          string   `json:"version"`
-	Author           string   `json:"author"`
 	Description      string   `json:"description"`
 	DownloadURL      string   `json:"download_url,omitempty"`
 	IconURL          string   `json:"icon_url,omitempty"`
@@ -83,7 +82,6 @@ type storeExtensionResponse struct {
 	Name             string   `json:"name"`
 	DisplayName      string   `json:"display_name"`
 	Version          string   `json:"version"`
-	Author           string   `json:"author"`
 	Description      string   `json:"description"`
 	DownloadURL      string   `json:"download_url"`
 	IconURL          string   `json:"icon_url,omitempty"`
@@ -103,7 +101,6 @@ func (e *storeExtension) toResponse() storeExtensionResponse {
 		Name:          e.Name,
 		DisplayName:   e.getDisplayName(),
 		Version:       e.Version,
-		Author:        e.Author,
 		Description:   e.Description,
 		DownloadURL:   e.getDownloadURL(),
 		IconURL:       e.getIconURL(),
@@ -253,7 +250,17 @@ func (s *extensionStore) fetchRegistry(forceRefresh bool) (*storeRegistry, error
 	LogInfo("ExtensionStore", "Fetching registry from %s", s.registryURL)
 
 	client := NewHTTPClientWithTimeout(30 * time.Second)
-	resp, err := client.Get(s.registryURL)
+	req, err := http.NewRequest(http.MethodGet, s.registryURL, nil)
+	if err != nil {
+		if s.cache != nil {
+			LogWarn("ExtensionStore", "Failed to build registry request, using cached registry: %v", err)
+			return s.cache, nil
+		}
+		return nil, fmt.Errorf("failed to build registry request: %w", err)
+	}
+	req.Header.Set("Cache-Control", "no-cache")
+	req.Header.Set("Pragma", "no-cache")
+	resp, err := client.Do(req)
 	if err != nil {
 		if s.cache != nil {
 			LogWarn("ExtensionStore", "Network error, using cached registry: %v", err)
@@ -348,7 +355,13 @@ func (s *extensionStore) downloadExtension(extensionID string, destPath string)
 	LogInfo("ExtensionStore", "Downloading %s from %s", ext.getDisplayName(), ext.getDownloadURL())
 
 	client := NewHTTPClientWithTimeout(5 * time.Minute)
-	resp, err := client.Get(ext.getDownloadURL())
+	req, err := http.NewRequest(http.MethodGet, ext.getDownloadURL(), nil)
+	if err != nil {
+		return fmt.Errorf("failed to build download request: %w", err)
+	}
+	req.Header.Set("Cache-Control", "no-cache")
+	req.Header.Set("Pragma", "no-cache")
+	resp, err := client.Do(req)
 	if err != nil {
 		return fmt.Errorf("failed to download: %w", err)
 	}
@@ -481,8 +494,7 @@ func (s *extensionStore) searchExtensions(query string, category string) ([]stor
 		if query != "" {
 			if !containsIgnoreCase(ext.Name, queryLower) &&
 				!containsIgnoreCase(ext.DisplayName, queryLower) &&
-				!containsIgnoreCase(ext.Description, queryLower) &&
-				!containsIgnoreCase(ext.Author, queryLower) {
+				!containsIgnoreCase(ext.Description, queryLower) {
 				found := false
 				for _, tag := range ext.Tags {
 					if containsIgnoreCase(tag, queryLower) {

go_backend/extension_test.go

@@ -1,8 +1,10 @@
 package gobackend
 
 import (
+	"net/http"
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/dop251/goja"
 )
@@ -12,7 +14,6 @@ func TestParseManifest_Valid(t *testing.T) {
 		"name": "test-provider",
 		"displayName": "Test Provider",
 		"version": "1.0.0",
-		"author": "Test Author",
 		"description": "A test extension",
 		"type": ["metadata_provider"],
 		"permissions": {
@@ -46,7 +47,6 @@ func TestParseManifest_Valid(t *testing.T) {
 func TestParseManifest_MissingName(t *testing.T) {
 	invalidManifest := `{
 		"version": "1.0.0",
-		"author": "Test Author",
 		"description": "A test extension",
 		"type": ["metadata_provider"]
 	}`
@@ -61,7 +61,6 @@ func TestParseManifest_MissingType(t *testing.T) {
 	invalidManifest := `{
 		"name": "test-provider",
 		"version": "1.0.0",
-		"author": "Test Author",
 		"description": "A test extension"
 	}`
 
@@ -239,6 +238,128 @@ func TestExtensionRuntime_UtilityFunctions(t *testing.T) {
 	if result.String() == "" {
 		t.Error("Expected non-empty JSON string")
 	}
+
+	result, err = vm.RunString(`utils.sleep(1)`)
+	if err != nil {
+		t.Fatalf("sleep failed: %v", err)
+	}
+	if !result.ToBoolean() {
+		t.Error("Expected sleep to complete successfully")
+	}
+
+	runtime.setActiveDownloadItemID("test-item")
+	cancelDownload("test-item")
+	t.Cleanup(func() {
+		clearDownloadCancel("test-item")
+		runtime.clearActiveDownloadItemID()
+	})
+
+	result, err = vm.RunString(`utils.isDownloadCancelled()`)
+	if err != nil {
+		t.Fatalf("isDownloadCancelled failed: %v", err)
+	}
+	if !result.ToBoolean() {
+		t.Error("Expected active download cancellation to be visible to JS")
+	}
+
+	SetAppVersion("4.2.2")
+	t.Cleanup(func() {
+		SetAppVersion("")
+	})
+
+	result, err = vm.RunString(`utils.appVersion()`)
+	if err != nil {
+		t.Fatalf("appVersion failed: %v", err)
+	}
+	if got := result.String(); got != "4.2.2" {
+		t.Fatalf("Expected appVersion 4.2.2, got %q", got)
+	}
+
+	result, err = vm.RunString(`utils.appUserAgent()`)
+	if err != nil {
+		t.Fatalf("appUserAgent failed: %v", err)
+	}
+	if got := result.String(); got != "SpotiFLAC-Mobile/4.2.2" {
+		t.Fatalf("Expected appUserAgent SpotiFLAC-Mobile/4.2.2, got %q", got)
+	}
+
+	result, err = vm.RunString(`utils.sleep(50)`)
+	if err != nil {
+		t.Fatalf("cancel-aware sleep failed: %v", err)
+	}
+	if result.ToBoolean() {
+		t.Error("Expected sleep to abort when download is cancelled")
+	}
+}
+
+func TestExtensionRuntime_BindDownloadCancelContext(t *testing.T) {
+	ext := &loadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+		},
+		DataDir: t.TempDir(),
+	}
+
+	runtime := newExtensionRuntime(ext)
+	runtime.setActiveDownloadItemID("test-item")
+	t.Cleanup(func() {
+		clearDownloadCancel("test-item")
+		runtime.clearActiveDownloadItemID()
+	})
+
+	req, err := http.NewRequest("GET", "https://api.example.com/test", nil)
+	if err != nil {
+		t.Fatalf("NewRequest failed: %v", err)
+	}
+
+	req = runtime.bindDownloadCancelContext(req)
+	cancelDownload("test-item")
+
+	select {
+	case <-req.Context().Done():
+	case <-time.After(500 * time.Millisecond):
+		t.Fatal("Expected bound request context to be cancelled")
+	}
+
+	if req.Context().Err() == nil {
+		t.Fatal("Expected request context error after cancellation")
+	}
+}
+
+func TestExtensionRuntime_BindDownloadCancelContextPreservesPreCancelledState(t *testing.T) {
+	ext := &loadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+		},
+		DataDir: t.TempDir(),
+	}
+
+	runtime := newExtensionRuntime(ext)
+	runtime.setActiveDownloadItemID("test-item")
+	cancelDownload("test-item")
+	t.Cleanup(func() {
+		clearDownloadCancel("test-item")
+		runtime.clearActiveDownloadItemID()
+	})
+
+	req, err := http.NewRequest("GET", "https://api.example.com/test", nil)
+	if err != nil {
+		t.Fatalf("NewRequest failed: %v", err)
+	}
+
+	req = runtime.bindDownloadCancelContext(req)
+
+	select {
+	case <-req.Context().Done():
+	case <-time.After(500 * time.Millisecond):
+		t.Fatal("Expected pre-cancelled request context to stay cancelled")
+	}
+
+	if req.Context().Err() == nil {
+		t.Fatal("Expected request context error for pre-cancelled item")
+	}
 }
 
 func TestExtensionRuntime_SSRFProtection(t *testing.T) {

go_backend/filename.go

@@ -6,6 +6,8 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	"unicode"
+	"unicode/utf8"
 )
 
 var (
@@ -17,19 +19,42 @@ var (
 )
 
 func sanitizeFilename(filename string) string {
-	sanitized := invalidChars.ReplaceAllString(filename, "_")
+	sanitized := strings.ReplaceAll(filename, "/", " ")
+	sanitized = invalidChars.ReplaceAllString(sanitized, " ")
 
+	var builder strings.Builder
+	for _, r := range sanitized {
+		if r < 0x20 && r != 0x09 && r != 0x0A && r != 0x0D {
+			continue
+		}
+		if r == 0x7F {
+			continue
+		}
+		if unicode.IsControl(r) && r != 0x09 && r != 0x0A && r != 0x0D {
+			continue
+		}
+		builder.WriteRune(r)
+	}
+
+	sanitized = builder.String()
 	sanitized = strings.TrimSpace(sanitized)
-	sanitized = strings.Trim(sanitized, ".")
-
+	sanitized = strings.Trim(sanitized, ". ")
+	sanitized = strings.Join(strings.Fields(sanitized), " ")
 	sanitized = multiUnderscore.ReplaceAllString(sanitized, "_")
+	sanitized = strings.Trim(sanitized, "_ ")
+
+	if !utf8.ValidString(sanitized) {
+		sanitized = strings.ToValidUTF8(sanitized, "_")
+	}
 
 	if len(sanitized) > 200 {
 		sanitized = sanitized[:200]
+		sanitized = strings.TrimSpace(strings.Trim(sanitized, ". "))
+		sanitized = strings.Trim(sanitized, "_ ")
 	}
 
 	if sanitized == "" {
-		sanitized = "untitled"
+		return "Unknown"
 	}
 
 	return sanitized

go_backend/filename_test.go

@@ -83,3 +83,18 @@ func TestBuildFilenameFromTemplate_DateStrftimeFormattingWithYearOnly(t *testing
 		t.Fatalf("expected %q, got %q", expected, formatted)
 	}
 }
+
+func TestSanitizeFilenameMatchesDesktopSpacingBehavior(t *testing.T) {
+	got := sanitizeFilename(`  "Text In Quotes"?%* / Demo  `)
+	want := "Text In Quotes % Demo"
+	if got != want {
+		t.Fatalf("expected %q, got %q", want, got)
+	}
+}
+
+func TestSanitizeFilenameFallsBackToUnknownWhenEmpty(t *testing.T) {
+	got := sanitizeFilename(`<>:"/\|?*`)
+	if got != "Unknown" {
+		t.Fatalf("expected %q, got %q", "Unknown", got)
+	}
+}

go_backend/httputil.go

@@ -16,6 +16,19 @@ import (
 	"time"
 )
 
+func userAgentForURL(u *url.URL) string {
+	if u == nil {
+		return getRandomUserAgent()
+	}
+
+	host := strings.ToLower(strings.TrimSpace(u.Hostname()))
+	if host == "api.zarz.moe" {
+		return appUserAgent()
+	}
+
+	return getRandomUserAgent()
+}
+
 func getRandomUserAgent() string {
 	chromeVersion := rand.Intn(26) + 120
 	chromeBuild := rand.Intn(1500) + 6000
@@ -225,7 +238,7 @@ func cloneRequestWithHTTPScheme(req *http.Request, scheme string) (*http.Request
 }
 
 func DoRequestWithUserAgent(client *http.Client, req *http.Request) (*http.Response, error) {
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", userAgentForURL(req.URL))
 	resp, err := client.Do(req)
 	if err != nil {
 		CheckAndLogISPBlocking(err, req.URL.String(), "HTTP")
@@ -255,7 +268,7 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 
 	for attempt := 0; attempt <= config.MaxRetries; attempt++ {
 		reqCopy := req.Clone(req.Context())
-		reqCopy.Header.Set("User-Agent", getRandomUserAgent())
+		reqCopy.Header.Set("User-Agent", userAgentForURL(reqCopy.URL))
 
 		resp, err := client.Do(reqCopy)
 		if err != nil {

go_backend/httputil_ios.go

@@ -11,7 +11,7 @@ func GetCloudflareBypassClient() *http.Client {
 }
 
 func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", userAgentForURL(req.URL))
 	resp, err := sharedClient.Do(req)
 	if err != nil {
 		CheckAndLogISPBlocking(err, req.URL.String(), "HTTP")

go_backend/httputil_utls.go

@@ -101,7 +101,7 @@ func GetCloudflareBypassClient() *http.Client {
 }
 
 func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", userAgentForURL(req.URL))
 
 	resp, err := sharedClient.Do(req)
 	if err == nil {
@@ -129,7 +129,7 @@ func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
 					LogDebug("HTTP", "Cloudflare detected, retrying with Chrome TLS fingerprint...")
 
 					reqCopy := req.Clone(req.Context())
-					reqCopy.Header.Set("User-Agent", getRandomUserAgent())
+					reqCopy.Header.Set("User-Agent", userAgentForURL(reqCopy.URL))
 
 					return cloudflareBypassClient.Do(reqCopy)
 				}
@@ -155,7 +155,7 @@ func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
 		LogDebug("HTTP", "TLS error detected, retrying with Chrome TLS fingerprint: %v", err)
 
 		reqCopy := req.Clone(req.Context())
-		reqCopy.Header.Set("User-Agent", getRandomUserAgent())
+		reqCopy.Header.Set("User-Agent", userAgentForURL(reqCopy.URL))
 
 		return cloudflareBypassClient.Do(reqCopy)
 	}

go_backend/lyrics.go

@@ -39,8 +39,34 @@ var DefaultLyricsProviders = []string{
 var (
 	lyricsProvidersMu sync.RWMutex
 	lyricsProviders   []string // ordered list of enabled providers
+	appVersionMu      sync.RWMutex
+	appVersion        string
 )
 
+func SetAppVersion(version string) {
+	normalized := strings.TrimSpace(version)
+
+	appVersionMu.Lock()
+	defer appVersionMu.Unlock()
+	appVersion = normalized
+}
+
+func GetAppVersion() string {
+	appVersionMu.RLock()
+	defer appVersionMu.RUnlock()
+	return appVersion
+}
+
+func appUserAgent() string {
+	version := GetAppVersion()
+
+	if version == "" {
+		return "SpotiFLAC-Mobile"
+	}
+
+	return "SpotiFLAC-Mobile/" + version
+}
+
 type LyricsFetchOptions struct {
 	IncludeTranslationNetease  bool   `json:"include_translation_netease"`
 	IncludeRomanizationNetease bool   `json:"include_romanization_netease"`

go_backend/lyrics_apple.go

@@ -114,7 +114,7 @@ func (c *AppleMusicClient) SearchSong(trackName, artistName string, durationSec
 		return "", fmt.Errorf("failed to create request: %w", err)
 	}
 
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
 	req.Header.Set("Accept", "application/json")
 
 	resp, err := c.httpClient.Do(req)
@@ -147,7 +147,8 @@ func (c *AppleMusicClient) FetchLyricsByID(songID string) (string, error) {
 	if err != nil {
 		return "", fmt.Errorf("failed to create request: %w", err)
 	}
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
+	req.Header.Set("Accept", "application/json")
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {

go_backend/lyrics_musixmatch.go

@@ -72,7 +72,7 @@ func (c *MusixmatchClient) fetchLyricsPayload(trackName, artistName string, dura
 		return "", fmt.Errorf("failed to create request: %w", err)
 	}
 	req.Header.Set("Accept", "application/json")
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {

go_backend/lyrics_netease.go

@@ -70,7 +70,7 @@ func (c *NeteaseClient) SearchSong(trackName, artistName string) (int64, error)
 	for k, v := range neteaseHeaders {
 		req.Header.Set(k, v)
 	}
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {
@@ -109,7 +109,7 @@ func (c *NeteaseClient) FetchLyricsByID(songID int64, includeTranslation, includ
 	for k, v := range neteaseHeaders {
 		req.Header.Set(k, v)
 	}
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {

go_backend/lyrics_qqmusic.go

@@ -54,7 +54,7 @@ func (c *QQMusicClient) fetchLyricsByMetadata(trackName, artistName string, dura
 	}
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("Accept", "application/json")
-	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("User-Agent", appUserAgent())
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {

go_backend/metadata.go

@@ -9,6 +9,7 @@ import (
 	_ "image/jpeg"
 	_ "image/png"
 	"io"
+	"math"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -1244,6 +1245,281 @@ func readM4AFreeformValue(f *os.File, parent atomHeader, fileSize int64) (string
 	return nameValue, dataValue, nil
 }
 
+type m4aMetadataPath struct {
+	moov atomHeader
+	udta *atomHeader
+	meta atomHeader
+	ilst atomHeader
+}
+
+func findM4AMetadataPath(f *os.File, fileSize int64) (m4aMetadataPath, error) {
+	moov, found, err := findAtomInRange(f, 0, fileSize, "moov", fileSize)
+	if err != nil || !found {
+		return m4aMetadataPath{}, fmt.Errorf("moov not found")
+	}
+
+	moovBodyStart := moov.offset + moov.headerSize
+	moovBodySize := moov.size - moov.headerSize
+
+	if udta, ok, _ := findAtomInRange(f, moovBodyStart, moovBodySize, "udta", fileSize); ok {
+		udtaBodyStart := udta.offset + udta.headerSize
+		udtaBodySize := udta.size - udta.headerSize
+		if meta, ok2, _ := findAtomInRange(f, udtaBodyStart, udtaBodySize, "meta", fileSize); ok2 {
+			metaBodyStart := meta.offset + meta.headerSize + 4
+			metaBodySize := meta.size - meta.headerSize - 4
+			if ilst, ok3, _ := findAtomInRange(f, metaBodyStart, metaBodySize, "ilst", fileSize); ok3 {
+				udtaCopy := udta
+				return m4aMetadataPath{
+					moov: moov,
+					udta: &udtaCopy,
+					meta: meta,
+					ilst: ilst,
+				}, nil
+			}
+		}
+	}
+
+	if meta, ok, _ := findAtomInRange(f, moovBodyStart, moovBodySize, "meta", fileSize); ok {
+		metaBodyStart := meta.offset + meta.headerSize + 4
+		metaBodySize := meta.size - meta.headerSize - 4
+		if ilst, ok2, _ := findAtomInRange(f, metaBodyStart, metaBodySize, "ilst", fileSize); ok2 {
+			return m4aMetadataPath{
+				moov: moov,
+				meta: meta,
+				ilst: ilst,
+			}, nil
+		}
+	}
+
+	return m4aMetadataPath{}, fmt.Errorf("ilst not found (tried moov>udta>meta>ilst and moov>meta>ilst)")
+}
+
+func buildM4AAtom(typ string, payload []byte) []byte {
+	size := int64(8 + len(payload))
+	buf := make([]byte, 8+len(payload))
+	binary.BigEndian.PutUint32(buf[0:4], uint32(size))
+	copy(buf[4:8], []byte(typ))
+	copy(buf[8:], payload)
+	return buf
+}
+
+func buildM4AFreeformAtom(name, value string) []byte {
+	meanPayload := append([]byte{0, 0, 0, 0}, []byte("com.apple.iTunes")...)
+	namePayload := append([]byte{0, 0, 0, 0}, []byte(name)...)
+	dataPayload := make([]byte, 8+len(value))
+	binary.BigEndian.PutUint32(dataPayload[0:4], 1) // UTF-8 text
+	copy(dataPayload[8:], []byte(value))
+
+	payload := append([]byte{}, buildM4AAtom("mean", meanPayload)...)
+	payload = append(payload, buildM4AAtom("name", namePayload)...)
+	payload = append(payload, buildM4AAtom("data", dataPayload)...)
+	return buildM4AAtom("----", payload)
+}
+
+func buildITunNORMTag(trackGain, trackPeak string) string {
+	gainDb, ok := parseReplayGainDb(trackGain)
+	if !ok {
+		return ""
+	}
+	peakLinear, ok := parseReplayGainPeak(trackPeak)
+	if !ok {
+		return ""
+	}
+
+	clamp := func(v int64) int64 {
+		if v < 0 {
+			return 0
+		}
+		if v > 65534 {
+			return 65534
+		}
+		return v
+	}
+
+	g1 := clamp(int64(math.Round(math.Pow(10, gainDb/-10.0) * 1000.0)))
+	g2 := clamp(int64(math.Round(math.Pow(10, gainDb/-10.0) * 2500.0)))
+	peak := clamp(int64(math.Round(peakLinear * 32768.0)))
+	values := []int64{g1, g1, g2, g2, 0, 0, peak, peak, 0, 0}
+	parts := make([]string, 0, len(values))
+	for _, value := range values {
+		parts = append(parts, strings.ToUpper(fmt.Sprintf("%08x", value)))
+	}
+	return strings.Join(parts, " ")
+}
+
+func parseReplayGainDb(value string) (float64, bool) {
+	match := regexp.MustCompile(`([+-]?\d+(?:\.\d+)?)`).FindStringSubmatch(strings.TrimSpace(value))
+	if len(match) < 2 {
+		return 0, false
+	}
+	parsed, err := strconv.ParseFloat(match[1], 64)
+	if err != nil {
+		return 0, false
+	}
+	return parsed, true
+}
+
+func parseReplayGainPeak(value string) (float64, bool) {
+	parsed, err := strconv.ParseFloat(strings.TrimSpace(value), 64)
+	if err != nil || parsed <= 0 {
+		return 0, false
+	}
+	return parsed, true
+}
+
+func collectM4AReplayGainFields(fields map[string]string) map[string]string {
+	result := map[string]string{}
+	if value := strings.TrimSpace(fields["replaygain_track_gain"]); value != "" {
+		result["replaygain_track_gain"] = value
+	}
+	if value := strings.TrimSpace(fields["replaygain_track_peak"]); value != "" {
+		result["replaygain_track_peak"] = value
+	}
+	if value := strings.TrimSpace(fields["replaygain_album_gain"]); value != "" {
+		result["replaygain_album_gain"] = value
+	}
+	if value := strings.TrimSpace(fields["replaygain_album_peak"]); value != "" {
+		result["replaygain_album_peak"] = value
+	}
+
+	if norm := buildITunNORMTag(result["replaygain_track_gain"], result["replaygain_track_peak"]); norm != "" {
+		result["iTunNORM"] = norm
+	}
+
+	return result
+}
+
+func writeAtomSize(buf []byte, header atomHeader, newSize int64) error {
+	if newSize <= 0 {
+		return fmt.Errorf("invalid size for %s", header.typ)
+	}
+	if header.headerSize == 16 {
+		if int(header.offset)+16 > len(buf) {
+			return io.ErrUnexpectedEOF
+		}
+		binary.BigEndian.PutUint32(buf[header.offset:header.offset+4], 1)
+		binary.BigEndian.PutUint64(buf[header.offset+8:header.offset+16], uint64(newSize))
+		return nil
+	}
+	if newSize > math.MaxUint32 {
+		return fmt.Errorf("atom %s too large for 32-bit header", header.typ)
+	}
+	if int(header.offset)+8 > len(buf) {
+		return io.ErrUnexpectedEOF
+	}
+	binary.BigEndian.PutUint32(buf[header.offset:header.offset+4], uint32(newSize))
+	return nil
+}
+
+func EditM4AReplayGain(filePath string, fields map[string]string) error {
+	replayGainFields := collectM4AReplayGainFields(fields)
+	if len(replayGainFields) == 0 {
+		return nil
+	}
+
+	f, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	info, err := f.Stat()
+	if err != nil {
+		return err
+	}
+
+	path, err := findM4AMetadataPath(f, info.Size())
+	if err != nil {
+		return err
+	}
+
+	data, err := os.ReadFile(filePath)
+	if err != nil {
+		return err
+	}
+
+	bodyStart := path.ilst.offset + path.ilst.headerSize
+	bodyEnd := path.ilst.offset + path.ilst.size
+	newBody := make([]byte, 0, int(path.ilst.size))
+	targets := map[string]struct{}{
+		"REPLAYGAIN_TRACK_GAIN": {},
+		"REPLAYGAIN_TRACK_PEAK": {},
+		"REPLAYGAIN_ALBUM_GAIN": {},
+		"REPLAYGAIN_ALBUM_PEAK": {},
+		"ITUNNORM":              {},
+	}
+
+	for pos := bodyStart; pos+8 <= bodyEnd; {
+		header, readErr := readAtomHeaderAt(f, pos, info.Size())
+		if readErr != nil {
+			return readErr
+		}
+		if header.size == 0 {
+			header.size = bodyEnd - pos
+		}
+		if header.size < header.headerSize {
+			return fmt.Errorf("invalid atom size for %s", header.typ)
+		}
+
+		keep := true
+		if header.typ == "----" {
+			name, _, freeformErr := readM4AFreeformValue(f, header, info.Size())
+			if freeformErr == nil {
+				if _, ok := targets[strings.ToUpper(strings.TrimSpace(name))]; ok {
+					keep = false
+				}
+			}
+		}
+		if keep {
+			newBody = append(newBody, data[pos:pos+header.size]...)
+		}
+
+		pos += header.size
+	}
+
+	order := []string{
+		"replaygain_track_gain",
+		"replaygain_track_peak",
+		"replaygain_album_gain",
+		"replaygain_album_peak",
+		"iTunNORM",
+	}
+	for _, key := range order {
+		value := strings.TrimSpace(replayGainFields[key])
+		if value == "" {
+			continue
+		}
+		name := key
+		if key != "iTunNORM" {
+			name = strings.ToLower(key)
+		}
+		newBody = append(newBody, buildM4AFreeformAtom(name, value)...)
+	}
+
+	newIlst := buildM4AAtom("ilst", newBody)
+	updated := append([]byte{}, data[:path.ilst.offset]...)
+	updated = append(updated, newIlst...)
+	updated = append(updated, data[path.ilst.offset+path.ilst.size:]...)
+
+	delta := int64(len(newIlst)) - path.ilst.size
+	if err := writeAtomSize(updated, path.ilst, path.ilst.size+delta); err != nil {
+		return err
+	}
+	if err := writeAtomSize(updated, path.meta, path.meta.size+delta); err != nil {
+		return err
+	}
+	if path.udta != nil {
+		if err := writeAtomSize(updated, *path.udta, path.udta.size+delta); err != nil {
+			return err
+		}
+	}
+	if err := writeAtomSize(updated, path.moov, path.moov.size+delta); err != nil {
+		return err
+	}
+
+	return os.WriteFile(filePath, updated, 0o644)
+}
+
 func extractLyricsFromSidecarLRC(filePath string) (string, error) {
 	ext := filepath.Ext(filePath)
 	base := strings.TrimSuffix(filePath, ext)
@@ -1423,16 +1699,82 @@ func GetM4AQuality(filePath string) (AudioQuality, error) {
 	//   [28:32] samplerate (16.16 fixed-point)
 	sampleRate := int(buf[28])<<8 | int(buf[29])
 	bitDepth := int(buf[22])<<8 | int(buf[23])
-	if bitDepth <= 0 {
-		bitDepth = 16
-		if atomType == "alac" {
-			bitDepth = 24
+
+	if atomType == "alac" {
+		if alacBitDepth, alacSampleRate, ok := readALACSpecificConfig(f, sampleOffset, fileSize); ok {
+			if alacBitDepth > 0 {
+				bitDepth = alacBitDepth
+			}
+			if alacSampleRate > 0 {
+				sampleRate = alacSampleRate
+			}
 		}
 	}
 
+	if bitDepth <= 0 {
+		bitDepth = 16
+	}
+
 	return AudioQuality{BitDepth: bitDepth, SampleRate: sampleRate}, nil
 }
 
+func readALACSpecificConfig(f *os.File, sampleOffset, fileSize int64) (int, int, bool) {
+	if sampleOffset < 4 {
+		return 0, 0, false
+	}
+
+	sampleEntryHeader, err := readAtomHeaderAt(f, sampleOffset-4, fileSize)
+	if err != nil {
+		return 0, 0, false
+	}
+
+	childStart := sampleOffset + 32
+	childEnd := sampleEntryHeader.offset + sampleEntryHeader.size
+	if childStart >= childEnd {
+		return 0, 0, false
+	}
+
+	configHeader, found, err := findAtomInRange(f, childStart, childEnd-childStart, "alac", fileSize)
+	if err != nil || !found {
+		return 0, 0, false
+	}
+
+	payloadSize := configHeader.size - configHeader.headerSize
+	if payloadSize <= 0 {
+		return 0, 0, false
+	}
+
+	payload := make([]byte, payloadSize)
+	if _, err := f.ReadAt(payload, configHeader.offset+configHeader.headerSize); err != nil {
+		return 0, 0, false
+	}
+
+	return parseALACSpecificConfig(payload)
+}
+
+func parseALACSpecificConfig(payload []byte) (int, int, bool) {
+	if len(payload) < 24 {
+		return 0, 0, false
+	}
+
+	bitDepth := int(payload[5])
+	sampleRate := int(binary.BigEndian.Uint32(payload[20:24]))
+	if bitDepth > 0 && sampleRate > 0 {
+		return bitDepth, sampleRate, true
+	}
+
+	// Some encoders prepend 4 bytes before the ALACSpecificConfig payload.
+	if len(payload) >= 28 {
+		bitDepth = int(payload[9])
+		sampleRate = int(binary.BigEndian.Uint32(payload[24:28]))
+		if bitDepth > 0 && sampleRate > 0 {
+			return bitDepth, sampleRate, true
+		}
+	}
+
+	return 0, 0, false
+}
+
 type atomHeader struct {
 	offset     int64
 	size       int64

go_backend/metadata_m4a_quality_test.go

@@ -0,0 +1,49 @@
+package gobackend
+
+import "testing"
+
+func TestParseALACSpecificConfigStandardPayload(t *testing.T) {
+	payload := make([]byte, 24)
+	payload[5] = 24
+	payload[20] = 0x00
+	payload[21] = 0x00
+	payload[22] = 0xac
+	payload[23] = 0x44
+
+	bitDepth, sampleRate, ok := parseALACSpecificConfig(payload)
+	if !ok {
+		t.Fatal("expected standard ALAC payload to parse")
+	}
+	if bitDepth != 24 {
+		t.Fatalf("bitDepth = %d, want 24", bitDepth)
+	}
+	if sampleRate != 44100 {
+		t.Fatalf("sampleRate = %d, want 44100", sampleRate)
+	}
+}
+
+func TestParseALACSpecificConfigPayloadWithLeadingFourBytes(t *testing.T) {
+	payload := make([]byte, 28)
+	payload[9] = 16
+	payload[24] = 0x00
+	payload[25] = 0x00
+	payload[26] = 0xbb
+	payload[27] = 0x80
+
+	bitDepth, sampleRate, ok := parseALACSpecificConfig(payload)
+	if !ok {
+		t.Fatal("expected offset ALAC payload to parse")
+	}
+	if bitDepth != 16 {
+		t.Fatalf("bitDepth = %d, want 16", bitDepth)
+	}
+	if sampleRate != 48000 {
+		t.Fatalf("sampleRate = %d, want 48000", sampleRate)
+	}
+}
+
+func TestParseALACSpecificConfigRejectsShortPayload(t *testing.T) {
+	if _, _, ok := parseALACSpecificConfig(make([]byte, 12)); ok {
+		t.Fatal("expected short ALAC payload to be rejected")
+	}
+}

go_backend/qobuz.go

@@ -2655,17 +2655,8 @@ func resolveQobuzTrackForRequest(req DownloadRequest, downloader *QobuzDownloade
 		}
 	}
 
-	// Strategy 5: Metadata search with strict matching (duration tolerance: 10 seconds)
 	if track == nil {
-		GoLog("[%s] Trying metadata search: '%s' by '%s'\n", logPrefix, req.TrackName, req.ArtistName)
-		track, err = qobuzSearchTrackByMetadataWithDurationFunc(downloader, req.TrackName, req.ArtistName, expectedDurationSec)
-		if track != nil && !qobuzTrackMatchesRequest(req, track, logPrefix, "metadata search", false) {
-			track = nil
-		}
-	}
-
-	if track == nil {
-		errMsg := "could not find matching track on Qobuz (artist/duration mismatch)"
+		errMsg := "could not find matching track on Qobuz without identifier match"
 		if err != nil {
 			errMsg = err.Error()
 		}

go_backend/qobuz_test.go

@@ -429,11 +429,9 @@ func TestResolveQobuzTrackForRequestRejectsOdesliMismatch(t *testing.T) {
 		t.Fatal("ISRC fallback should not run without an ISRC")
 		return nil, nil
 	}
-	qobuzSearchTrackByMetadataWithDurationFunc = func(_ *QobuzDownloader, trackName, artistName string, expectedDurationSec int) (*QobuzTrack, error) {
-		if trackName != "Taste Back" || artistName != "Harry Styles" || expectedDurationSec != 181 {
-			t.Fatalf("unexpected metadata fallback arguments: %q / %q / %d", trackName, artistName, expectedDurationSec)
-		}
-		return testQobuzTrack(444, "Taste Back", "Harry Styles", 181), nil
+	qobuzSearchTrackByMetadataWithDurationFunc = func(_ *QobuzDownloader, _, _ string, _ int) (*QobuzTrack, error) {
+		t.Fatal("metadata fallback should not run")
+		return nil, nil
 	}
 	songLinkCheckTrackAvailabilityFunc = func(_ *SongLinkClient, _, _ string) (*TrackAvailability, error) {
 		t.Fatal("SongLink should not run when Odesli QobuzID is provided")
@@ -448,11 +446,11 @@ func TestResolveQobuzTrackForRequestRejectsOdesliMismatch(t *testing.T) {
 	}
 
 	track, err := resolveQobuzTrackForRequest(req, &QobuzDownloader{}, "Test")
-	if err != nil {
-		t.Fatalf("expected no error, got %v", err)
+	if err == nil {
+		t.Fatalf("expected error, got track %+v", track)
 	}
-	if track == nil || track.ID != 444 || track.Title != "Taste Back" {
-		t.Fatalf("unexpected resolved track: %+v", track)
+	if track != nil {
+		t.Fatalf("expected nil track, got %+v", track)
 	}
 }
 

go_backend/songlink.go

@@ -147,6 +147,7 @@ func (s *SongLinkClient) doResolveRequest(payload []byte) (map[string]songLinkPl
 		return nil, fmt.Errorf("failed to create resolve request: %w", err)
 	}
 	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("User-Agent", userAgentForURL(req.URL))
 
 	resp, err := s.client.Do(req)
 	if err != nil {
@@ -164,9 +165,9 @@ func (s *SongLinkClient) doResolveRequest(payload []byte) (map[string]songLinkPl
 	}
 
 	var resolveResp struct {
-		Success  bool                           `json:"success"`
-		ISRC     string                         `json:"isrc"`
-		SongUrls map[string]json.RawMessage     `json:"songUrls"`
+		Success  bool                       `json:"success"`
+		ISRC     string                     `json:"isrc"`
+		SongUrls map[string]json.RawMessage `json:"songUrls"`
 	}
 	if err := json.Unmarshal(body, &resolveResp); err != nil {
 		return nil, fmt.Errorf("failed to decode resolve response: %w", err)

go_backend/tidal.go

@@ -51,6 +51,7 @@ type TidalTrack struct {
 	ID           int64  `json:"id"`
 	Title        string `json:"title"`
 	ISRC         string `json:"isrc"`
+	Copyright    string `json:"copyright"`
 	AudioQuality string `json:"audioQuality"`
 	TrackNumber  int    `json:"trackNumber"`
 	VolumeNumber int    `json:"volumeNumber"`
@@ -135,6 +136,7 @@ type tidalPublicAlbum struct {
 	Type           string              `json:"type"`
 	Cover          string              `json:"cover"`
 	ReleaseDate    string              `json:"releaseDate"`
+	Copyright      string              `json:"copyright"`
 	URL            string              `json:"url"`
 	NumberOfTracks int                 `json:"numberOfTracks"`
 	Explicit       bool                `json:"explicit"`
@@ -306,6 +308,29 @@ func tidalTrackArtistsDisplay(track *TidalTrack) string {
 	return strings.TrimSpace(track.Artist.Name)
 }
 
+func tidalTrackAlbumArtistDisplay(track *TidalTrack) string {
+	if track == nil {
+		return ""
+	}
+
+	if len(track.Artists) > 0 {
+		names := make([]string, 0, len(track.Artists))
+		for _, artist := range track.Artists {
+			if strings.ToUpper(strings.TrimSpace(artist.Type)) != "MAIN" {
+				continue
+			}
+			if trimmed := strings.TrimSpace(artist.Name); trimmed != "" {
+				names = append(names, trimmed)
+			}
+		}
+		if len(names) > 0 {
+			return strings.Join(names, ", ")
+		}
+	}
+
+	return strings.TrimSpace(track.Artist.Name)
+}
+
 func tidalAlbumArtistsDisplay(album *tidalPublicAlbum) string {
 	if album == nil {
 		return ""
@@ -354,7 +379,7 @@ func tidalTrackToTrackMetadata(track *TidalTrack) TrackMetadata {
 		Artists:     tidalTrackArtistsDisplay(track),
 		Name:        strings.TrimSpace(track.Title),
 		AlbumName:   strings.TrimSpace(track.Album.Title),
-		AlbumArtist: strings.TrimSpace(track.Artist.Name),
+		AlbumArtist: tidalTrackAlbumArtistDisplay(track),
 		DurationMS:  track.Duration * 1000,
 		Images:      tidalImageURL(track.Album.Cover, "1280x1280"),
 		ReleaseDate: strings.TrimSpace(track.Album.ReleaseDate),
@@ -377,7 +402,7 @@ func tidalTrackToAlbumTrackMetadata(track *TidalTrack) AlbumTrackMetadata {
 		Artists:     tidalTrackArtistsDisplay(track),
 		Name:        strings.TrimSpace(track.Title),
 		AlbumName:   strings.TrimSpace(track.Album.Title),
-		AlbumArtist: strings.TrimSpace(track.Artist.Name),
+		AlbumArtist: tidalTrackAlbumArtistDisplay(track),
 		DurationMS:  track.Duration * 1000,
 		Images:      tidalImageURL(track.Album.Cover, "1280x1280"),
 		ReleaseDate: strings.TrimSpace(track.Album.ReleaseDate),
@@ -407,6 +432,7 @@ func tidalAlbumToAlbumInfo(album *tidalPublicAlbum) AlbumInfoMetadata {
 		Artists:     tidalAlbumArtistsDisplay(album),
 		ArtistId:    artistID,
 		Images:      tidalImageURL(album.Cover, "1280x1280"),
+		Copyright:   strings.TrimSpace(album.Copyright),
 	}
 }
 
@@ -688,6 +714,10 @@ func findTidalArtistPageModule(page *tidalPublicArtistPage, moduleType string) *
 
 func (t *TidalDownloader) GetAvailableAPIs() []string {
 	return []string{
+		"https://eu-central.monochrome.tf",
+		"https://us-west.monochrome.tf",
+		"https://api.monochrome.tf",
+		"https://monochrome-api.samidy.com",
 		"https://tidal-api.binimum.org",
 		"https://tidal.kinoplus.online",
 		"https://triton.squid.wtf",
@@ -1736,6 +1766,7 @@ type TidalDownloadResult struct {
 	TrackNumber int
 	DiscNumber  int
 	ISRC        string
+	Copyright   string
 	LyricsLRC   string // LRC content for embedding in converted files
 }
 
@@ -2049,18 +2080,6 @@ func resolveTidalTrackForRequest(req DownloadRequest, downloader *TidalDownloade
 		}
 	}
 
-	if !gotTidalID && req.ISRC != "" {
-		GoLog("[%s] Trying direct Tidal ISRC search: %s\n", logPrefix, req.ISRC)
-		directTrack, directErr := downloader.SearchTrackByISRC(req.ISRC)
-		if directErr == nil && directTrack != nil && directTrack.ID > 0 {
-			trackID = directTrack.ID
-			gotTidalID = true
-			GoLog("[%s] Got Tidal ID %d from direct ISRC search\n", logPrefix, trackID)
-		} else if directErr != nil {
-			GoLog("[%s] Direct Tidal ISRC search failed: %v\n", logPrefix, directErr)
-		}
-	}
-
 	if !gotTidalID && req.ISRC != "" && req.TrackName != "" && req.ArtistName != "" {
 		GoLog("[%s] Trying Tidal public metadata search with ISRC\n", logPrefix)
 		searchTrack, searchErr := downloader.SearchTrackByMetadataWithISRC(
@@ -2356,6 +2375,10 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 	if actualDiscNumber == 0 {
 		actualDiscNumber = track.VolumeNumber
 	}
+	copyright := strings.TrimSpace(req.Copyright)
+	if copyright == "" {
+		copyright = strings.TrimSpace(track.Copyright)
+	}
 
 	metadata := Metadata{
 		Title:         req.TrackName,
@@ -2371,7 +2394,7 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		ISRC:          track.ISRC,
 		Genre:         req.Genre,
 		Label:         req.Label,
-		Copyright:     req.Copyright,
+		Copyright:     copyright,
 		Composer:      req.Composer,
 	}
 
@@ -2482,6 +2505,7 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		TrackNumber: resultTrackNumber,
 		DiscNumber:  resultDiscNumber,
 		ISRC:        track.ISRC,
+		Copyright:   copyright,
 		LyricsLRC:   lyricsLRC,
 	}, nil
 }

ios/Runner/AppDelegate.swift

@@ -22,6 +22,9 @@ import Gobackend  // Import Go framework
         _ application: UIApplication,
         didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
     ) -> Bool {
+        if let version = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String {
+            GobackendSetAppVersion(version)
+        }
         
         let controller = window?.rootViewController as! FlutterViewController
         let channel = FlutterMethodChannel(
@@ -66,9 +69,59 @@ import Gobackend  // Import Go framework
         )
         
         GeneratedPluginRegistrant.register(with: self)
+        if let url = launchOptions?[.url] as? URL {
+            _ = handleExtensionOAuthRedirect(url: url)
+        }
         return super.application(application, didFinishLaunchingWithOptions: launchOptions)
     }
 
+    /// PKCE OAuth return URL: spotiflac://callback?code=...&state=<extension_id>
+    @discardableResult
+    private func handleExtensionOAuthRedirect(url: URL) -> Bool {
+        guard let scheme = url.scheme?.lowercased(), scheme == "spotiflac" else { return false }
+        let host = (url.host ?? "").lowercased()
+        let path = url.path.lowercased()
+        let ok =
+            host == "callback" || host == "spotify-callback" || path.contains("callback")
+        guard ok else { return false }
+        guard let components = URLComponents(url: url, resolvingAgainstBaseURL: false) else {
+            return false
+        }
+        let q = components.queryItems ?? []
+        let code =
+            q.first { $0.name == "code" }?.value?.trimmingCharacters(
+                in: .whitespacesAndNewlines) ?? ""
+        let state =
+            q.first { $0.name == "state" }?.value?.trimmingCharacters(
+                in: .whitespacesAndNewlines) ?? ""
+        if code.isEmpty { return false }
+        if state.isEmpty {
+            NSLog("SpotiFLAC: Extension OAuth redirect missing state (extension id)")
+            return false
+        }
+        streamQueue.async {
+            var err: NSError?
+            GobackendSetExtensionAuthCodeByID(state, code)
+            _ = GobackendInvokeExtensionActionJSON(state, "completeSpotifyLogin", &err)
+            if let err = err {
+                NSLog(
+                    "SpotiFLAC: Extension OAuth complete failed: \(err.localizedDescription)")
+            }
+        }
+        return true
+    }
+
+    override func application(
+        _ app: UIApplication,
+        open url: URL,
+        options: [UIApplication.OpenURLOptionsKey: Any] = [:]
+    ) -> Bool {
+        if handleExtensionOAuthRedirect(url: url) {
+            return true
+        }
+        return super.application(app, open: url, options: options)
+    }
+
     deinit {
         stopDownloadProgressStream()
         stopLibraryScanProgressStream()
@@ -371,16 +424,6 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
-        case "searchDeezerAll":
-            let args = call.arguments as! [String: Any]
-            let query = args["query"] as! String
-            let trackLimit = args["track_limit"] as? Int ?? 15
-            let artistLimit = args["artist_limit"] as? Int ?? 3
-            let filter = args["filter"] as? String ?? ""
-            let response = GobackendSearchDeezerAll(query, Int(trackLimit), Int(artistLimit), filter, &error)
-            if let error = error { throw error }
-            return response
-
         case "searchTidalAll":
             let args = call.arguments as! [String: Any]
             let query = args["query"] as! String

lib/constants/app_info.dart

@@ -3,8 +3,8 @@ import 'package:flutter/foundation.dart';
 /// App version and info constants
 /// Update version here only - all other files will reference this
 class AppInfo {
-  static const String version = '4.2.2';
-  static const String buildNumber = '123';
+  static const String version = '4.3.1';
+  static const String buildNumber = '126';
   static const String fullVersion = '$version+$buildNumber';
 
   /// Shows "Internal" in debug builds, actual version in release.

lib/l10n/app_localizations.dart

@@ -352,6 +352,18 @@ abstract class AppLocalizations {
   /// **'Using extension: {extensionName}'**
   String optionsUsingExtension(String extensionName);
 
+  /// Title for the preferred default search tab setting
+  ///
+  /// In en, this message translates to:
+  /// **'Default Search Tab'**
+  String get optionsDefaultSearchTab;
+
+  /// Subtitle for the preferred default search tab setting
+  ///
+  /// In en, this message translates to:
+  /// **'Choose which tab opens first for new search results.'**
+  String get optionsDefaultSearchTabSubtitle;
+
   /// Hint to switch back to built-in providers
   ///
   /// In en, this message translates to:
@@ -718,6 +730,12 @@ abstract class AppLocalizations {
   /// **'PC source code'**
   String get aboutPCSource;
 
+  /// Link to Keep Android Open campaign website
+  ///
+  /// In en, this message translates to:
+  /// **'Keep Android Open'**
+  String get aboutKeepAndroidOpen;
+
   /// Link to report bugs
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_de.dart

@@ -129,6 +129,13 @@ class AppLocalizationsDe extends AppLocalizations {
     return 'Erweiterung verwenden: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tippe auf Deezer oder Spotify, um von der Erweiterung zurückzuwechseln';
@@ -341,6 +348,9 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC Quellcode';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Problem melden';
 

lib/l10n/app_localizations_en.dart

@@ -127,6 +127,13 @@ class AppLocalizationsEn extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 

lib/l10n/app_localizations_es.dart

@@ -127,6 +127,13 @@ class AppLocalizationsEs extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsEs extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 
@@ -3707,6 +3717,9 @@ class AppLocalizationsEsEs extends AppLocalizationsEs {
   @override
   String get aboutPCSource => 'Código fuente de PC';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Reportar un problema';
 

lib/l10n/app_localizations_fr.dart

@@ -128,6 +128,13 @@ class AppLocalizationsFr extends AppLocalizations {
     return 'Utilisation de l\'extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Appuyez sur Deezer ou Spotify pour revenir à l\'extension';
@@ -336,6 +343,9 @@ class AppLocalizationsFr extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 

lib/l10n/app_localizations_hi.dart

@@ -127,6 +127,13 @@ class AppLocalizationsHi extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 

lib/l10n/app_localizations_id.dart

@@ -129,6 +129,13 @@ class AppLocalizationsId extends AppLocalizations {
     return 'Menggunakan ekstensi: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Tab Pencarian Default';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Pilih tab yang dibuka lebih dulu untuk hasil pencarian baru.';
+
   @override
   String get optionsSwitchBack =>
       'Ketuk Deezer atau Spotify untuk beralih dari ekstensi';
@@ -337,6 +344,9 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get aboutPCSource => 'Kode sumber PC';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Laporkan masalah';
 

lib/l10n/app_localizations_ja.dart

@@ -127,6 +127,13 @@ class AppLocalizationsJa extends AppLocalizations {
     return '拡張の使用: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -330,6 +337,9 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC 版のソースコード';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => '問題を報告する';
 

lib/l10n/app_localizations_ko.dart

@@ -125,6 +125,13 @@ class AppLocalizationsKo extends AppLocalizations {
     return '확장 기능을 사용: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack => 'Deezer 또는 Spotify를 탭하여 확장 기능에서 다시 전환하세요.';
 
@@ -323,6 +330,9 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC 소스 코드';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => '문제 신고';
 

lib/l10n/app_localizations_nl.dart

@@ -127,6 +127,13 @@ class AppLocalizationsNl extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 

lib/l10n/app_localizations_pt.dart

@@ -127,6 +127,13 @@ class AppLocalizationsPt extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsPt extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 
@@ -3707,6 +3717,9 @@ class AppLocalizationsPtPt extends AppLocalizationsPt {
   @override
   String get aboutPCSource => 'Código-fonte do app desktop';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Reportar um problema';
 

lib/l10n/app_localizations_ru.dart

@@ -129,6 +129,13 @@ class AppLocalizationsRu extends AppLocalizations {
     return 'Используется расширение: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Нажмите Deezer или Spotify для возврата с расширения';
@@ -340,6 +347,9 @@ class AppLocalizationsRu extends AppLocalizations {
   @override
   String get aboutPCSource => 'Исходный код ПК версии';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Сообщить о проблеме';
 

lib/l10n/app_localizations_zh.dart

@@ -127,6 +127,13 @@ class AppLocalizationsZh extends AppLocalizations {
     return 'Using extension: $extensionName';
   }
 
+  @override
+  String get optionsDefaultSearchTab => 'Default Search Tab';
+
+  @override
+  String get optionsDefaultSearchTabSubtitle =>
+      'Choose which tab opens first for new search results.';
+
   @override
   String get optionsSwitchBack =>
       'Tap Deezer or Spotify to switch back from extension';
@@ -334,6 +341,9 @@ class AppLocalizationsZh extends AppLocalizations {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 
@@ -3689,6 +3699,9 @@ class AppLocalizationsZhCn extends AppLocalizationsZh {
   @override
   String get aboutPCSource => '桌面版本源代码';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => '报告一个问题';
 
@@ -6083,6 +6096,9 @@ class AppLocalizationsZhTw extends AppLocalizationsZh {
   @override
   String get aboutPCSource => 'PC source code';
 
+  @override
+  String get aboutKeepAndroidOpen => 'Keep Android Open';
+
   @override
   String get aboutReportIssue => 'Report an issue';
 

lib/l10n/arb/app_de.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Problem melden",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_en.arb

@@ -158,6 +158,14 @@
       }
     }
   },
+  "optionsDefaultSearchTab": "Default Search Tab",
+  "@optionsDefaultSearchTab": {
+    "description": "Title for the preferred default search tab setting"
+  },
+  "optionsDefaultSearchTabSubtitle": "Choose which tab opens first for new search results.",
+  "@optionsDefaultSearchTabSubtitle": {
+    "description": "Subtitle for the preferred default search tab setting"
+  },
   "optionsSwitchBack": "Tap Deezer or Spotify to switch back from extension",
   "@optionsSwitchBack": {
     "description": "Hint to switch back to built-in providers"
@@ -422,6 +430,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_es.arb

@@ -362,6 +362,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_es_ES.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Reportar un problema",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_fr.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_hi.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_id.arb

@@ -150,6 +150,14 @@
       }
     }
   },
+  "optionsDefaultSearchTab": "Tab Pencarian Default",
+  "@optionsDefaultSearchTab": {
+    "description": "Title for the preferred default search tab setting"
+  },
+  "optionsDefaultSearchTabSubtitle": "Pilih tab yang dibuka lebih dulu untuk hasil pencarian baru.",
+  "@optionsDefaultSearchTabSubtitle": {
+    "description": "Subtitle for the preferred default search tab setting"
+  },
   "optionsSwitchBack": "Ketuk Deezer atau Spotify untuk beralih dari ekstensi",
   "@optionsSwitchBack": {
     "description": "Hint to switch back to built-in providers"
@@ -382,6 +390,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Laporkan masalah",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_ja.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "問題を報告する",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_ko.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "문제 신고",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_nl.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_pt.arb

@@ -362,6 +362,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_pt_PT.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Reportar um problema",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_ru.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Сообщить о проблеме",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_zh.arb

@@ -362,6 +362,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_zh_CN.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "报告一个问题",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/l10n/arb/app_zh_TW.arb

@@ -378,6 +378,10 @@
   "@aboutPCSource": {
     "description": "Link to PC GitHub repo"
   },
+  "aboutKeepAndroidOpen": "Keep Android Open",
+  "@aboutKeepAndroidOpen": {
+    "description": "Link to Keep Android Open campaign website"
+  },
   "aboutReportIssue": "Report an issue",
   "@aboutReportIssue": {
     "description": "Link to report bugs"

lib/models/settings.dart

@@ -35,6 +35,7 @@ class AppSettings {
   final bool useExtensionProviders;
   final List<String>? downloadFallbackExtensionIds;
   final String? searchProvider;
+  final String defaultSearchTab;
   final String? homeFeedProvider;
   final bool separateSingles;
   final String singleFilenameFormat;
@@ -111,6 +112,7 @@ class AppSettings {
     this.useExtensionProviders = true,
     this.downloadFallbackExtensionIds,
     this.searchProvider,
+    this.defaultSearchTab = 'all',
     this.homeFeedProvider,
     this.separateSingles = false,
     this.singleFilenameFormat = '{title} - {artist}',
@@ -176,6 +178,7 @@ class AppSettings {
     bool clearDownloadFallbackExtensionIds = false,
     String? searchProvider,
     bool clearSearchProvider = false,
+    String? defaultSearchTab,
     String? homeFeedProvider,
     bool clearHomeFeedProvider = false,
     bool? separateSingles,
@@ -242,6 +245,7 @@ class AppSettings {
       searchProvider: clearSearchProvider
           ? null
           : (searchProvider ?? this.searchProvider),
+      defaultSearchTab: defaultSearchTab ?? this.defaultSearchTab,
       homeFeedProvider: clearHomeFeedProvider
           ? null
           : (homeFeedProvider ?? this.homeFeedProvider),

lib/models/settings.g.dart

@@ -40,6 +40,7 @@ AppSettings _$AppSettingsFromJson(Map<String, dynamic> json) => AppSettings(
           ?.map((e) => e as String)
           .toList(),
   searchProvider: json['searchProvider'] as String?,
+  defaultSearchTab: json['defaultSearchTab'] as String? ?? 'all',
   homeFeedProvider: json['homeFeedProvider'] as String?,
   separateSingles: json['separateSingles'] as bool? ?? false,
   singleFilenameFormat:
@@ -111,6 +112,7 @@ Map<String, dynamic> _$AppSettingsToJson(
   'useExtensionProviders': instance.useExtensionProviders,
   'downloadFallbackExtensionIds': instance.downloadFallbackExtensionIds,
   'searchProvider': instance.searchProvider,
+  'defaultSearchTab': instance.defaultSearchTab,
   'homeFeedProvider': instance.homeFeedProvider,
   'separateSingles': instance.separateSingles,
   'singleFilenameFormat': instance.singleFilenameFormat,

lib/providers/download_queue_provider.dart

@@ -26,7 +26,10 @@ final _log = AppLogger('DownloadQueue');
 final _historyLog = AppLogger('DownloadHistory');
 
 final _invalidFolderChars = RegExp(r'[<>:"/\\|?*]');
-final _trailingDotsRegex = RegExp(r'\.+$');
+final _trimDotsAndSpacesRegex = RegExp(r'^[. ]+|[. ]+$');
+final _trimUnderscoresAndSpacesRegex = RegExp(r'^[_ ]+|[_ ]+$');
+final _multiWhitespaceRegex = RegExp(r'\s+');
+final _multiUnderscoreRegex = RegExp(r'_+');
 
 /// log10 helper using dart:math's natural log.
 double _log10(num x) => log(x) / ln10;
@@ -571,6 +574,7 @@ class DownloadHistoryNotifier extends Notifier<DownloadHistoryState> {
     if (trimmed.startsWith('content://')) return true;
     return trimmed.endsWith('.flac') ||
         trimmed.endsWith('.m4a') ||
+        trimmed.endsWith('.mp4') ||
         trimmed.endsWith('.aac') ||
         trimmed.endsWith('.mp3') ||
         trimmed.endsWith('.opus') ||
@@ -592,6 +596,7 @@ class DownloadHistoryNotifier extends Notifier<DownloadHistoryState> {
         !hasResolvedSpecs &&
         (trimmedPath.endsWith('.flac') ||
             trimmedPath.endsWith('.m4a') ||
+            trimmedPath.endsWith('.mp4') ||
             trimmedPath.endsWith('.aac') ||
             trimmedPath.startsWith('content://'));
 
@@ -2165,10 +2170,29 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
   }
 
   String _sanitizeFolderName(String name) {
-    return name
-        .replaceAll(_invalidFolderChars, '_')
-        .replaceAll(_trailingDotsRegex, '')
-        .trim();
+    final buffer = StringBuffer();
+    for (final rune in name.runes) {
+      if (rune < 0x20 || rune == 0x7f) {
+        continue;
+      }
+      final char = String.fromCharCode(rune);
+      if (_invalidFolderChars.hasMatch(char)) {
+        buffer.write(' ');
+        continue;
+      }
+      buffer.write(char);
+    }
+
+    var sanitized = buffer.toString().trim();
+    sanitized = sanitized.replaceAll(_trimDotsAndSpacesRegex, '');
+    sanitized = sanitized.replaceAll(_multiWhitespaceRegex, ' ');
+    sanitized = sanitized.replaceAll(_multiUnderscoreRegex, '_');
+    sanitized = sanitized.replaceAll(_trimUnderscoresAndSpacesRegex, '');
+
+    if (sanitized.isEmpty) {
+      return 'Unknown';
+    }
+    return sanitized;
   }
 
   static final _featuredArtistPattern = RegExp(
@@ -2322,11 +2346,59 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
     return '$prefix/$suffix';
   }
 
+  String? _extensionPreferredOutputExt(String service) {
+    final normalizedService = service.trim().toLowerCase();
+    if (normalizedService.isEmpty) return null;
+
+    final extensionState = ref.read(extensionProvider);
+    for (final ext in extensionState.extensions) {
+      if (!ext.enabled || !ext.hasDownloadProvider) continue;
+      if (ext.id.toLowerCase() != normalizedService) continue;
+
+      final preferred = ext.preferredDownloadOutputExtension;
+      if (preferred == null) return null;
+
+      final normalized = preferred.startsWith('.')
+          ? preferred.toLowerCase()
+          : '.${preferred.toLowerCase()}';
+      if (normalized == '.mp4') {
+        return '.m4a';
+      }
+      const allowed = <String>{'.flac', '.m4a', '.mp3', '.opus'};
+      if (allowed.contains(normalized)) {
+        return normalized;
+      }
+      return null;
+    }
+
+    return null;
+  }
+
+  bool _extensionPreservesNativeOutputExt(String service, String ext) {
+    final normalizedService = service.trim().toLowerCase();
+    final normalizedExt = ext.trim().toLowerCase();
+    if (normalizedService.isEmpty || normalizedExt.isEmpty) return false;
+
+    final extensionState = ref.read(extensionProvider);
+    return extensionState.extensions.any(
+      (ext) =>
+          ext.enabled &&
+          ext.hasDownloadProvider &&
+          ext.id.toLowerCase() == normalizedService &&
+          ext.preservedNativeOutputExtensions.contains(normalizedExt),
+    );
+  }
+
   String _determineOutputExt(String quality, String service) {
+    final extensionPreferred = _extensionPreferredOutputExt(service);
+    if (extensionPreferred != null) {
+      return extensionPreferred;
+    }
     if (service.toLowerCase() == 'tidal' && quality == 'HIGH') {
       return '.m4a';
     }
     final q = quality.toLowerCase();
+    if (q == 'alac' || q.startsWith('aac')) return '.m4a';
     if (q.startsWith('opus')) return '.opus';
     if (q.startsWith('mp3')) return '.mp3';
     return '.flac';
@@ -2335,6 +2407,7 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
   String _mimeTypeForExt(String ext) {
     switch (ext.toLowerCase()) {
       case '.m4a':
+      case '.mp4':
         return 'audio/mp4';
       case '.mp3':
         return 'audio/mpeg';
@@ -3637,6 +3710,8 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
   ) {
     final backendTrackNum = _parsePositiveInt(backendResult['track_number']);
     final backendDiscNum = _parsePositiveInt(backendResult['disc_number']);
+    final backendTotalTracks = _parsePositiveInt(backendResult['total_tracks']);
+    final backendTotalDiscs = _parsePositiveInt(backendResult['total_discs']);
     final backendYear = normalizeOptionalString(
       backendResult['release_date'] as String?,
     );
@@ -3664,7 +3739,9 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         backendIsrc != null ||
         backendCoverUrl != null ||
         backendAlbumArtist != null ||
-        backendComposer != null;
+        backendComposer != null ||
+        backendTotalTracks != null ||
+        backendTotalDiscs != null;
 
     if (!hasOverrides) {
       return baseTrack;
@@ -3683,12 +3760,12 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
       isrc: backendIsrc ?? baseTrack.isrc,
       trackNumber: backendTrackNum ?? baseTrack.trackNumber,
       discNumber: backendDiscNum ?? baseTrack.discNumber,
-      totalDiscs: baseTrack.totalDiscs,
+      totalDiscs: backendTotalDiscs ?? baseTrack.totalDiscs,
       releaseDate: backendYear ?? baseTrack.releaseDate,
       deezerId: baseTrack.deezerId,
       availability: baseTrack.availability,
       albumType: baseTrack.albumType,
-      totalTracks: baseTrack.totalTracks,
+      totalTracks: backendTotalTracks ?? baseTrack.totalTracks,
       composer: backendComposer ?? baseTrack.composer,
       source: baseTrack.source,
     );
@@ -3696,8 +3773,8 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
 
   /// Unified metadata, cover, lyrics, and ReplayGain embedding for all formats.
   ///
-  /// [format] must be one of `'flac'`, `'mp3'`, or `'opus'`.
-  /// [writeExternalLrc] only applies to FLAC (non-SAF paths handle LRC separately).
+  /// [format] must be one of `'flac'`, `'m4a'`, `'mp3'`, or `'opus'`.
+  /// [writeExternalLrc] only applies to FLAC and M4A (non-SAF paths handle LRC separately).
   Future<void> _embedMetadataToFile(
     String filePath,
     Track track, {
@@ -3717,6 +3794,7 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
     }
 
     final isFlac = format == 'flac';
+    final isM4a = format == 'm4a';
     final isMp3 = format == 'mp3';
 
     // ── Cover download ──────────────────────────────────────────────
@@ -3840,9 +3918,11 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
       if (shouldEmbedLyrics && lrcContent != null) {
         metadata['LYRICS'] = lrcContent;
         if (isFlac || isMp3) metadata['UNSYNCEDLYRICS'] = lrcContent;
-      } else if (isFlac && !shouldEmbedLyrics) {
+      } else if ((isFlac || isM4a) && !shouldEmbedLyrics) {
         metadata['LYRICS'] = '';
-        metadata['UNSYNCEDLYRICS'] = '';
+        if (isFlac) {
+          metadata['UNSYNCEDLYRICS'] = '';
+        }
       }
 
       if (writeExternalLrc && shouldSaveExternalLyrics && lrcContent != null) {
@@ -3856,11 +3936,14 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         }
       }
 
-      // ── ReplayGain (MP3/Opus: scan before FFmpeg, add to metadata) ─
+      ReplayGainResult? scannedReplayGain;
+
+      // ── ReplayGain (MP3/Opus/M4A: scan before FFmpeg, add to metadata) ─
       if (settings.embedReplayGain && !isFlac) {
         try {
           final rgResult = await FFmpegService.scanReplayGain(filePath);
           if (rgResult != null) {
+            scannedReplayGain = rgResult;
             metadata['REPLAYGAIN_TRACK_GAIN'] = rgResult.trackGain;
             metadata['REPLAYGAIN_TRACK_PEAK'] = rgResult.trackPeak;
             _log.d(
@@ -3886,6 +3969,12 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
           metadata: metadata,
           artistTagMode: settings.artistTagMode,
         );
+      } else if (isM4a) {
+        ffmpegResult = await FFmpegService.embedMetadataToM4a(
+          m4aPath: filePath,
+          coverPath: validCover,
+          metadata: metadata,
+        );
       } else if (isMp3) {
         ffmpegResult = await FFmpegService.embedMetadataToMp3(
           mp3Path: filePath,
@@ -3907,6 +3996,20 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         _log.w('FFmpeg $format metadata embed failed');
       }
 
+      if (isM4a && settings.embedReplayGain && scannedReplayGain != null) {
+        try {
+          await PlatformBridge.editFileMetadata(filePath, {
+            'replaygain_track_gain': scannedReplayGain.trackGain,
+            'replaygain_track_peak': scannedReplayGain.trackPeak,
+          });
+          _log.d(
+            'ReplayGain compatibility tags written for $format: gain=${scannedReplayGain.trackGain}, peak=${scannedReplayGain.trackPeak}',
+          );
+        } catch (e) {
+          _log.w('Failed to write native ReplayGain tags for $format: $e');
+        }
+      }
+
       // ── FLAC post-processing ────────────────────────────────────────
       if (isFlac) {
         if (settings.artistTagMode == artistTagModeSplitVorbis) {
@@ -4795,6 +4898,10 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         final actualService =
             ((result['service'] as String?)?.toLowerCase()) ??
             item.service.toLowerCase();
+        final preferredOutputExt = _extensionPreferredOutputExt(actualService);
+        final shouldPreserveNativeM4a =
+            preferredOutputExt == '.m4a' ||
+            _extensionPreservesNativeOutputExt(actualService, '.m4a');
         final decryptionDescriptor =
             DownloadDecryptionDescriptor.fromDownloadResult(result);
         trackToDownload = _buildTrackForMetadataEmbedding(
@@ -4920,6 +5027,7 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         final isM4aFile =
             filePath != null &&
             (filePath.endsWith('.m4a') ||
+                filePath.endsWith('.mp4') ||
                 (mimeType != null && mimeType.contains('mp4')));
         final isFlacFile =
             filePath != null &&
@@ -4935,7 +5043,7 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
 
         if (shouldForceTidalSafM4aHandling) {
           _log.w(
-            'Tidal SAF file is labeled FLAC but backend returned DASH/M4A stream; forcing FFmpeg conversion to FLAC.',
+            'Tidal SAF file is labeled FLAC but backend returned DASH/M4A stream; converting it back to FLAC.',
           );
         }
 
@@ -5052,6 +5160,64 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
                   }
                 }
               }
+            } else if (shouldPreserveNativeM4a) {
+              _log.d('M4A file detected (SAF), preserving native container...');
+              final tempPath = await _copySafToTemp(currentFilePath);
+              if (tempPath != null) {
+                try {
+                  if (metadataEmbeddingEnabled) {
+                    updateItemStatus(
+                      item.id,
+                      DownloadStatus.finalizing,
+                      progress: 0.99,
+                    );
+                    final finalTrack = _buildTrackForMetadataEmbedding(
+                      trackToDownload,
+                      result,
+                      resolvedAlbumArtist,
+                    );
+                    final backendGenre = result['genre'] as String?;
+                    final backendLabel = result['label'] as String?;
+                    final backendCopyright = result['copyright'] as String?;
+
+                    await _embedMetadataToFile(
+                      tempPath,
+                      finalTrack,
+                      format: 'm4a',
+                      genre: backendGenre ?? genre,
+                      label: backendLabel ?? label,
+                      copyright: backendCopyright,
+                      downloadService: item.service,
+                      writeExternalLrc: false,
+                    );
+                  }
+
+                  final newFileName = '${safBaseName ?? 'track'}.m4a';
+                  final newUri = await _writeTempToSaf(
+                    treeUri: settings.downloadTreeUri,
+                    relativeDir: effectiveOutputDir,
+                    fileName: newFileName,
+                    mimeType: _mimeTypeForExt('.m4a'),
+                    srcPath: tempPath,
+                  );
+
+                  if (newUri != null) {
+                    if (newUri != currentFilePath) {
+                      await _deleteSafFile(currentFilePath);
+                    }
+                    filePath = newUri;
+                    finalSafFileName = newFileName;
+                  } else {
+                    _log.w('Failed to write M4A to SAF, keeping original');
+                  }
+                } catch (e) {
+                  _log.w('SAF native M4A handling failed: $e');
+                } finally {
+                  try {
+                    await File(tempPath).delete();
+                  } catch (_) {}
+                }
+              }
             } else {
               _log.d('M4A file detected (SAF), converting to FLAC...');
               final tempPath = await _copySafToTemp(currentFilePath);
@@ -5207,6 +5373,61 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
                 _log.w('M4A conversion process failed: $e, keeping M4A file');
                 actualQuality = 'AAC 320kbps';
               }
+            } else if (shouldPreserveNativeM4a) {
+              _log.d('M4A file detected, preserving native container...');
+
+              try {
+                var targetPath = currentFilePath;
+                final file = File(targetPath);
+                if (!await file.exists()) {
+                  _log.e('File does not exist at path: $filePath');
+                } else {
+                  if (!(targetPath.toLowerCase().endsWith('.m4a') ||
+                      targetPath.toLowerCase().endsWith('.mp4'))) {
+                    final renamedPath = targetPath.replaceAll(
+                      RegExp(r'\.[^.]+$'),
+                      '.m4a',
+                    );
+                    final finalRenamedPath = renamedPath == targetPath
+                        ? '$targetPath.m4a'
+                        : renamedPath;
+                    await file.rename(finalRenamedPath);
+                    targetPath = finalRenamedPath;
+                    filePath = finalRenamedPath;
+                  } else {
+                    filePath = targetPath;
+                  }
+
+                  if (metadataEmbeddingEnabled) {
+                    updateItemStatus(
+                      item.id,
+                      DownloadStatus.finalizing,
+                      progress: 0.99,
+                    );
+                    final finalTrack = _buildTrackForMetadataEmbedding(
+                      trackToDownload,
+                      result,
+                      resolvedAlbumArtist,
+                    );
+
+                    final backendGenre = result['genre'] as String?;
+                    final backendLabel = result['label'] as String?;
+                    final backendCopyright = result['copyright'] as String?;
+
+                    await _embedMetadataToFile(
+                      targetPath,
+                      finalTrack,
+                      format: 'm4a',
+                      genre: backendGenre ?? genre,
+                      label: backendLabel ?? label,
+                      copyright: backendCopyright,
+                      downloadService: item.service,
+                    );
+                  }
+                }
+              } catch (e) {
+                _log.w('Native M4A handling failed: $e');
+              }
             } else {
               _log.d(
                 'M4A file detected (Hi-Res DASH stream), attempting conversion to FLAC...',
@@ -5599,12 +5820,15 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
           final backendYear = result['release_date'] as String?;
           final backendTrackNum = result['track_number'] as int?;
           final backendDiscNum = result['disc_number'] as int?;
+          final backendTotalTracks = result['total_tracks'] as int?;
+          final backendTotalDiscs = result['total_discs'] as int?;
           final backendBitDepth = result['actual_bit_depth'] as int?;
           final backendSampleRate = result['actual_sample_rate'] as int?;
           final backendISRC = result['isrc'] as String?;
           final backendGenre = result['genre'] as String?;
           final backendLabel = result['label'] as String?;
           final backendCopyright = result['copyright'] as String?;
+          final backendComposer = result['composer'] as String?;
           final effectiveGenre =
               normalizeOptionalString(backendGenre) ??
               normalizeOptionalString(genre) ??
@@ -5625,6 +5849,7 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
               filePath.startsWith('content://') ||
               lowerFilePath.endsWith('.flac') ||
               lowerFilePath.endsWith('.m4a') ||
+              lowerFilePath.endsWith('.mp4') ||
               lowerFilePath.endsWith('.aac') ||
               lowerFilePath.endsWith('.mp3') ||
               lowerFilePath.endsWith('.opus') ||
@@ -5712,11 +5937,17 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
                   trackNumber: (backendTrackNum != null && backendTrackNum > 0)
                       ? backendTrackNum
                       : trackToDownload.trackNumber,
-                  totalTracks: trackToDownload.totalTracks,
+                  totalTracks:
+                      (backendTotalTracks != null && backendTotalTracks > 0)
+                      ? backendTotalTracks
+                      : trackToDownload.totalTracks,
                   discNumber: (backendDiscNum != null && backendDiscNum > 0)
                       ? backendDiscNum
                       : trackToDownload.discNumber,
-                  totalDiscs: trackToDownload.totalDiscs,
+                  totalDiscs:
+                      (backendTotalDiscs != null && backendTotalDiscs > 0)
+                      ? backendTotalDiscs
+                      : trackToDownload.totalDiscs,
                   duration: trackToDownload.duration,
                   releaseDate: (backendYear != null && backendYear.isNotEmpty)
                       ? backendYear
@@ -5725,7 +5956,10 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
                   bitDepth: historyBitDepth,
                   sampleRate: historySampleRate,
                   genre: effectiveGenre,
-                  composer: trackToDownload.composer,
+                  composer:
+                      (backendComposer != null && backendComposer.isNotEmpty)
+                      ? backendComposer
+                      : trackToDownload.composer,
                   label: effectiveLabel,
                   copyright: effectiveCopyright,
                 ),

lib/providers/extension_provider.dart

@@ -20,7 +20,6 @@ class Extension {
   final String name;
   final String displayName;
   final String version;
-  final String author;
   final String description;
   final bool enabled;
   final String status;
@@ -45,7 +44,6 @@ class Extension {
     required this.name,
     required this.displayName,
     required this.version,
-    required this.author,
     required this.description,
     required this.enabled,
     required this.status,
@@ -73,7 +71,6 @@ class Extension {
       displayName:
           json['display_name'] as String? ?? json['name'] as String? ?? '',
       version: json['version'] as String? ?? '0.0.0',
-      author: json['author'] as String? ?? 'Unknown',
       description: json['description'] as String? ?? '',
       enabled: json['enabled'] as bool? ?? false,
       status: json['status'] as String? ?? 'loaded',
@@ -124,7 +121,6 @@ class Extension {
     String? name,
     String? displayName,
     String? version,
-    String? author,
     String? description,
     bool? enabled,
     String? status,
@@ -149,7 +145,6 @@ class Extension {
       name: name ?? this.name,
       displayName: displayName ?? this.displayName,
       version: version ?? this.version,
-      author: author ?? this.author,
       description: description ?? this.description,
       enabled: enabled ?? this.enabled,
       status: status ?? this.status,
@@ -178,6 +173,26 @@ class Extension {
   bool get hasPostProcessing => postProcessing?.enabled ?? false;
   bool get hasHomeFeed => capabilities['homeFeed'] == true;
   bool get hasBrowseCategories => capabilities['browseCategories'] == true;
+  String? get preferredDownloadOutputExtension {
+    final value = capabilities['downloadOutputExtension'];
+    if (value is! String) return null;
+    final trimmed = value.trim();
+    return trimmed.isEmpty ? null : trimmed;
+  }
+
+  List<String> get preservedNativeOutputExtensions {
+    final value = capabilities['preserveNativeOutputExtensions'];
+    if (value is! List) return const [];
+
+    final normalized = <String>[];
+    for (final item in value) {
+      if (item is! String) continue;
+      final trimmed = item.trim().toLowerCase();
+      if (trimmed.isEmpty) continue;
+      normalized.add(trimmed.startsWith('.') ? trimmed : '.$trimmed');
+    }
+    return normalized;
+  }
 }
 
 class SearchFilter {
@@ -481,8 +496,10 @@ class ExtensionState {
 }
 
 class ExtensionNotifier extends Notifier<ExtensionState> {
+  static const _builtInMetadataProviders = ['qobuz', 'tidal'];
   AppLifecycleListener? _appLifecycleListener;
   bool _cleanupInFlight = false;
+  Completer<void>? _initializationCompleter;
 
   @override
   ExtensionState build() {
@@ -520,6 +537,13 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
 
   Future<void> initialize(String extensionsDir, String dataDir) async {
     if (state.isInitialized) return;
+    if (_initializationCompleter != null) {
+      await _initializationCompleter!.future;
+      return;
+    }
+
+    final completer = Completer<void>();
+    _initializationCompleter = completer;
 
     state = state.copyWith(isLoading: true, error: null);
 
@@ -531,6 +555,8 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
         error: null,
       );
       _log.i('Extension system disabled on this platform');
+      completer.complete();
+      _initializationCompleter = null;
       return;
     }
 
@@ -544,6 +570,32 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
     } catch (e) {
       _log.e('Failed to initialize extension system: $e');
       state = state.copyWith(isLoading: false, error: e.toString());
+    } finally {
+      if (!completer.isCompleted) {
+        completer.complete();
+      }
+      if (identical(_initializationCompleter, completer)) {
+        _initializationCompleter = null;
+      }
+    }
+  }
+
+  Future<void> waitForInitialization({
+    Duration timeout = const Duration(seconds: 30),
+  }) async {
+    if (state.isInitialized || !PlatformBridge.supportsExtensionSystem) {
+      return;
+    }
+
+    final future = _initializationCompleter?.future;
+    if (future == null) {
+      return;
+    }
+
+    try {
+      await future.timeout(timeout);
+    } on TimeoutException {
+      _log.w('Timed out waiting for extension initialization after $timeout');
     }
   }
 
@@ -566,6 +618,7 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
       final list = await PlatformBridge.getInstalledExtensions();
       final extensions = list.map((e) => Extension.fromJson(e)).toList();
       state = state.copyWith(extensions: extensions);
+      await _reconcileDownloadProviderPriority();
       _log.d('Loaded ${extensions.length} extensions');
 
       for (final ext in extensions) {
@@ -661,6 +714,7 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
       }).toList();
 
       state = state.copyWith(extensions: extensions);
+      await _reconcileDownloadProviderPriority();
 
       if (!enabled && ext != null) {
         final settings = ref.read(settingsProvider);
@@ -685,6 +739,23 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
     }
   }
 
+  Future<void> _reconcileDownloadProviderPriority() async {
+    if (state.providerPriority.isEmpty) {
+      return;
+    }
+
+    final sanitized = _sanitizeDownloadProviderPriority(state.providerPriority);
+    if (jsonEncode(sanitized) == jsonEncode(state.providerPriority)) {
+      return;
+    }
+
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setString(_providerPriorityKey, jsonEncode(sanitized));
+    await PlatformBridge.setProviderPriority(sanitized);
+    state = state.copyWith(providerPriority: sanitized);
+    _log.d('Reconciled provider priority after extension update: $sanitized');
+  }
+
   Future<bool> ensureSpotifyWebExtensionReady({
     bool setAsSearchProvider = true,
   }) async {
@@ -812,6 +883,7 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
 
   List<String> _sanitizeDownloadProviderPriority(List<String> input) {
     final allowed = getAllDownloadProviders().toSet();
+    final preferredOrder = getAllDownloadProviders();
     final result = <String>[];
 
     for (final provider in input) {
@@ -820,7 +892,7 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
       }
     }
 
-    for (final provider in const ['tidal', 'qobuz']) {
+    for (final provider in preferredOrder) {
       if (!result.contains(provider)) {
         result.add(provider);
       }
@@ -847,10 +919,15 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
         );
         await PlatformBridge.setMetadataProviderPriority(priority);
       } else {
-        priority = _sanitizeMetadataProviderPriority(
-          await PlatformBridge.getMetadataProviderPriority(),
-        );
+        final backendPriority =
+            await PlatformBridge.getMetadataProviderPriority();
+        priority = _sanitizeMetadataProviderPriority(backendPriority);
         _log.d('Using default metadata provider priority: $priority');
+        await prefs.setString(
+          _metadataProviderPriorityKey,
+          jsonEncode(priority),
+        );
+        await PlatformBridge.setMetadataProviderPriority(priority);
       }
 
       state = state.copyWith(metadataProviderPriority: priority);
@@ -906,17 +983,26 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
   }
 
   List<String> getAllMetadataProviders() {
-    final providers = ['deezer', 'qobuz', 'tidal'];
-    for (final ext in state.extensions) {
-      if (ext.enabled && ext.hasMetadataProvider) {
-        providers.add(ext.id);
-      }
-    }
-    return providers;
+    final metadataExtensions = state.extensions
+        .where((ext) => ext.enabled && ext.hasMetadataProvider)
+        .toList();
+    final primarySearchMetadataExtensions = metadataExtensions
+        .where((ext) => ext.searchBehavior?.primary == true)
+        .map((ext) => ext.id);
+    final otherMetadataExtensions = metadataExtensions
+        .where((ext) => ext.searchBehavior?.primary != true)
+        .map((ext) => ext.id);
+
+    return [
+      ...primarySearchMetadataExtensions,
+      ..._builtInMetadataProviders,
+      ...otherMetadataExtensions,
+    ];
   }
 
   List<String> _sanitizeMetadataProviderPriority(List<String> input) {
     final allowed = getAllMetadataProviders().toSet();
+    final preferredOrder = getAllMetadataProviders();
     final result = <String>[];
 
     for (final provider in input) {
@@ -925,7 +1011,18 @@ class ExtensionNotifier extends Notifier<ExtensionState> {
       }
     }
 
-    for (final provider in const ['deezer', 'qobuz', 'tidal']) {
+    final hasPreferredExtension = preferredOrder.any(
+      (provider) => !_builtInMetadataProviders.contains(provider),
+    );
+    final hasSavedExtension = result.any(
+      (provider) => !_builtInMetadataProviders.contains(provider),
+    );
+
+    if (!hasSavedExtension && hasPreferredExtension) {
+      return List<String>.from(preferredOrder);
+    }
+
+    for (final provider in preferredOrder) {
       if (!result.contains(provider)) {
         result.add(provider);
       }

lib/providers/settings_provider.dart

@@ -18,6 +18,7 @@ final _log = AppLogger('SettingsProvider');
 
 class SettingsNotifier extends Notifier<AppSettings> {
   static final RegExp _isoRegionPattern = RegExp(r'^[A-Z]{2}$');
+  static const Set<String> _searchTabValues = {'all', 'track', 'artist', 'album'};
 
   final Future<SharedPreferences> _prefs = SharedPreferences.getInstance();
   final FlutterSecureStorage _secureStorage = const FlutterSecureStorage();
@@ -42,11 +43,15 @@ class SettingsNotifier extends Notifier<AppSettings> {
           _sanitizeDownloadFallbackExtensionIds(
             loaded.downloadFallbackExtensionIds,
           );
+      final sanitizedDefaultSearchTab = _normalizeDefaultSearchTab(
+        loaded.defaultSearchTab,
+      );
       state = loaded.copyWith(
         downloadFallbackExtensionIds: sanitizedDownloadFallbackExtensionIds,
         clearDownloadFallbackExtensionIds:
             loaded.downloadFallbackExtensionIds != null &&
             sanitizedDownloadFallbackExtensionIds == null,
+        defaultSearchTab: sanitizedDefaultSearchTab,
       );
 
       await _runMigrations(prefs);
@@ -187,6 +192,12 @@ class SettingsNotifier extends Notifier<AppSettings> {
     return 'US';
   }
 
+  String _normalizeDefaultSearchTab(String value) {
+    final normalized = value.trim().toLowerCase();
+    if (_searchTabValues.contains(normalized)) return normalized;
+    return 'all';
+  }
+
   Future<void> _normalizeSongLinkRegionIfNeeded() async {
     final normalized = _normalizeSongLinkRegion(state.songLinkRegion);
     if (normalized == state.songLinkRegion) return;
@@ -408,6 +419,11 @@ class SettingsNotifier extends Notifier<AppSettings> {
     _saveSettings();
   }
 
+  void setDefaultSearchTab(String tab) {
+    state = state.copyWith(defaultSearchTab: _normalizeDefaultSearchTab(tab));
+    _saveSettings();
+  }
+
   void setHomeFeedProvider(String? provider) {
     if (provider == null || provider.isEmpty) {
       state = state.copyWith(clearHomeFeedProvider: true);

lib/providers/store_provider.dart

@@ -63,7 +63,6 @@ class StoreExtension {
   final String name;
   final String displayName;
   final String version;
-  final String author;
   final String description;
   final String downloadUrl;
   final String? iconUrl;
@@ -81,7 +80,6 @@ class StoreExtension {
     required this.name,
     required this.displayName,
     required this.version,
-    required this.author,
     required this.description,
     required this.downloadUrl,
     this.iconUrl,
@@ -102,7 +100,6 @@ class StoreExtension {
       displayName:
           json['display_name'] as String? ?? json['name'] as String? ?? '',
       version: json['version'] as String? ?? '0.0.0',
-      author: json['author'] as String? ?? 'Unknown',
       description: json['description'] as String? ?? '',
       downloadUrl: json['download_url'] as String? ?? '',
       iconUrl: json['icon_url'] as String?,
@@ -194,7 +191,6 @@ class StoreState {
                 e.name.toLowerCase().contains(query) ||
                 e.displayName.toLowerCase().contains(query) ||
                 e.description.toLowerCase().contains(query) ||
-                e.author.toLowerCase().contains(query) ||
                 e.tags.any((t) => t.toLowerCase().contains(query)),
           )
           .toList();

lib/providers/track_provider.dart

@@ -7,6 +7,7 @@ import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/providers/extension_provider.dart';
 
 final _log = AppLogger('TrackProvider');
+const _extensionInitRetryTimeout = Duration(seconds: 30);
 
 class TrackState {
   final List<Track> tracks;
@@ -203,13 +204,36 @@ class TrackNotifier extends Notifier<TrackState> {
 
   bool _isRequestValid(int requestId) => requestId == _currentRequestId;
 
+  bool _usesBuiltInUrlResolver(String url) {
+    final normalized = url.toLowerCase();
+    return normalized.contains('deezer.com') ||
+        normalized.contains('deezer.page.link') ||
+        normalized.contains('qobuz.com') ||
+        normalized.startsWith('qobuzapp://') ||
+        normalized.contains('tidal.com');
+  }
+
   Future<void> fetchFromUrl(String url, {bool useDeezerFallback = true}) async {
     final requestId = ++_currentRequestId;
 
     state = TrackState(isLoading: true, hasSearchText: state.hasSearchText);
 
     try {
-      final extensionHandler = await PlatformBridge.findURLHandler(url);
+      var extensionHandler = await PlatformBridge.findURLHandler(url);
+      if (extensionHandler == null && !_usesBuiltInUrlResolver(url)) {
+        final extensionState = ref.read(extensionProvider);
+        if (!extensionState.isInitialized && extensionState.isLoading) {
+          _log.i(
+            'Extension URL handlers not ready yet, waiting for initialization...',
+          );
+          await ref
+              .read(extensionProvider.notifier)
+              .waitForInitialization(timeout: _extensionInitRetryTimeout);
+          if (!_isRequestValid(requestId)) return;
+          extensionHandler = await PlatformBridge.findURLHandler(url);
+        }
+      }
+
       if (extensionHandler != null) {
         _log.i('Found extension URL handler: $extensionHandler for URL: $url');
 
@@ -559,8 +583,99 @@ class TrackNotifier extends Notifier<TrackState> {
     String? builtInSearchProvider,
   }) async {
     final requestId = ++_currentRequestId;
-
     final currentFilter = filterOverride ?? state.selectedSearchFilter;
+    final requestFilter = currentFilter == 'all' ? null : currentFilter;
+    final settings = ref.read(settingsProvider);
+    final extensionState = ref.read(extensionProvider);
+
+    String? resolvedProvider = builtInSearchProvider;
+    if (resolvedProvider == null || resolvedProvider.isEmpty) {
+      final explicitProvider = settings.searchProvider?.trim();
+      if (explicitProvider != null && explicitProvider.isNotEmpty) {
+        resolvedProvider = explicitProvider;
+      } else {
+        resolvedProvider =
+            extensionState.extensions
+                .where(
+                  (ext) =>
+                      ext.enabled &&
+                      ext.hasCustomSearch &&
+                      ext.searchBehavior?.primary == true,
+                )
+                .map((ext) => ext.id)
+                .firstOrNull ??
+            extensionState.extensions
+                .where((ext) => ext.enabled && ext.hasCustomSearch)
+                .map((ext) => ext.id)
+                .firstOrNull;
+      }
+      resolvedProvider ??= 'tidal';
+    }
+
+    final isEnabledExtensionProvider =
+        resolvedProvider.isNotEmpty &&
+        extensionState.extensions.any(
+          (ext) => ext.enabled && ext.id == resolvedProvider,
+        );
+
+    if (resolvedProvider.isNotEmpty &&
+        resolvedProvider != 'tidal' &&
+        resolvedProvider != 'qobuz' &&
+        !isEnabledExtensionProvider &&
+        settings.searchProvider?.trim() == resolvedProvider) {
+      ref.read(settingsProvider.notifier).setSearchProvider(null);
+      resolvedProvider =
+          extensionState.extensions
+              .where(
+                (ext) =>
+                    ext.enabled &&
+                    ext.hasCustomSearch &&
+                    ext.searchBehavior?.primary == true,
+              )
+              .map((ext) => ext.id)
+              .firstOrNull ??
+          extensionState.extensions
+              .where((ext) => ext.enabled && ext.hasCustomSearch)
+              .map((ext) => ext.id)
+              .firstOrNull;
+      resolvedProvider ??= 'tidal';
+    }
+
+    if (resolvedProvider.isNotEmpty &&
+        resolvedProvider != 'tidal' &&
+        resolvedProvider != 'qobuz' &&
+        extensionState.extensions.any(
+          (ext) => ext.enabled && ext.id == resolvedProvider,
+        )) {
+      final resolvedFilter = requestFilter ?? 'track';
+      Map<String, dynamic>? options;
+      options = {'filter': resolvedFilter};
+      await customSearch(
+        resolvedProvider,
+        query,
+        options: options,
+        selectedFilter: resolvedFilter,
+      );
+      return;
+    }
+
+    final effectiveBuiltInProvider =
+        resolvedProvider == 'tidal' || resolvedProvider == 'qobuz'
+        ? resolvedProvider
+        : (builtInSearchProvider?.isNotEmpty == true
+              ? builtInSearchProvider
+              : 'tidal');
+
+    if (effectiveBuiltInProvider == null || effectiveBuiltInProvider.isEmpty) {
+      state = TrackState(
+        isLoading: false,
+        error: 'No active search provider available',
+        hasSearchText: state.hasSearchText,
+        isShowingRecentAccess: state.isShowingRecentAccess,
+        selectedSearchFilter: currentFilter,
+      );
+      return;
+    }
 
     state = TrackState(
       isLoading: true,
@@ -570,42 +685,21 @@ class TrackNotifier extends Notifier<TrackState> {
     );
 
     try {
-      final settings = ref.read(settingsProvider);
-      final extensionState = ref.read(extensionProvider);
       final hasActiveMetadataExtensions = extensionState.extensions.any(
         (e) => e.enabled && e.hasMetadataProvider,
       );
       final includeExtensions =
           settings.useExtensionProviders && hasActiveMetadataExtensions;
 
-      final effectiveProvider = builtInSearchProvider ?? 'deezer';
+      final effectiveProvider = effectiveBuiltInProvider;
 
       _log.i(
-        'Search started: provider=$effectiveProvider, query="$query", includeExtensions=$includeExtensions, filter=$currentFilter',
+        'Search started: provider=$effectiveProvider, query="$query", includeExtensions=$includeExtensions, filter=$requestFilter',
       );
 
       Map<String, dynamic> results;
       List<Map<String, dynamic>> metadataTrackResults = [];
 
-      if (effectiveProvider == 'deezer') {
-        try {
-          _log.d('Calling metadata provider search API...');
-          metadataTrackResults =
-              await PlatformBridge.searchTracksWithMetadataProviders(
-                query,
-                limit: 20,
-                includeExtensions: includeExtensions,
-              );
-          _log.i(
-            'Metadata providers returned ${metadataTrackResults.length} tracks',
-          );
-        } catch (e) {
-          _log.w(
-            'Metadata provider search failed, falling back to Deezer tracks: $e',
-          );
-        }
-      }
-
       switch (effectiveProvider) {
         case 'tidal':
           _log.d('Calling Tidal search API...');
@@ -613,7 +707,7 @@ class TrackNotifier extends Notifier<TrackState> {
             query,
             trackLimit: 20,
             artistLimit: 2,
-            filter: currentFilter,
+            filter: requestFilter,
           );
           break;
         case 'qobuz':
@@ -622,17 +716,23 @@ class TrackNotifier extends Notifier<TrackState> {
             query,
             trackLimit: 20,
             artistLimit: 2,
-            filter: currentFilter,
+            filter: requestFilter,
           );
           break;
         default:
-          _log.d('Calling Deezer search API...');
-          results = await PlatformBridge.searchDeezerAll(
-            query,
-            trackLimit: 20,
-            artistLimit: 2,
-            filter: currentFilter,
-          );
+          _log.d('Calling metadata provider track search API...');
+          metadataTrackResults =
+              await PlatformBridge.searchTracksWithMetadataProviders(
+                query,
+                limit: 20,
+                includeExtensions: includeExtensions,
+              );
+          results = const <String, List<dynamic>>{
+            'tracks': <dynamic>[],
+            'artists': <dynamic>[],
+            'albums': <dynamic>[],
+            'playlists': <dynamic>[],
+          };
           break;
       }
       _log.i(
@@ -741,14 +841,16 @@ class TrackNotifier extends Notifier<TrackState> {
     String extensionId,
     String query, {
     Map<String, dynamic>? options,
+    String? selectedFilter,
   }) async {
     final requestId = ++_currentRequestId;
+    final currentFilter = selectedFilter ?? state.selectedSearchFilter;
 
     state = TrackState(
       isLoading: true,
       hasSearchText: state.hasSearchText,
       isShowingRecentAccess: state.isShowingRecentAccess,
-      selectedSearchFilter: state.selectedSearchFilter,
+      selectedSearchFilter: currentFilter,
     );
 
     try {
@@ -788,7 +890,7 @@ class TrackNotifier extends Notifier<TrackState> {
         hasSearchText: state.hasSearchText,
         isShowingRecentAccess: state.isShowingRecentAccess,
         searchExtensionId: extensionId,
-        selectedSearchFilter: state.selectedSearchFilter,
+        selectedSearchFilter: currentFilter,
       );
     } catch (e, stackTrace) {
       if (!_isRequestValid(requestId)) return;
@@ -798,6 +900,7 @@ class TrackNotifier extends Notifier<TrackState> {
         error: e.toString(),
         hasSearchText: state.hasSearchText,
         isShowingRecentAccess: state.isShowingRecentAccess,
+        selectedSearchFilter: currentFilter,
       );
     }
   }

lib/screens/home_tab.dart

@@ -426,14 +426,18 @@ class _HomeTabState extends ConsumerState<HomeTab>
     String? currentSearchProvider,
     List<Extension> extensions,
   ) {
+    final resolvedSearchProvider = _resolveSearchProvider(
+      currentSearchProvider,
+      extensions,
+    );
     final isUsingExtensionSearch =
-        currentSearchProvider != null &&
-        currentSearchProvider.isNotEmpty &&
-        extensions.any((e) => e.id == currentSearchProvider && e.enabled);
+        resolvedSearchProvider != null &&
+        resolvedSearchProvider.isNotEmpty &&
+        extensions.any((e) => e.id == resolvedSearchProvider && e.enabled);
 
     if (isUsingExtensionSearch) {
       final currentSearchExtension = extensions
-          .where((e) => e.id == currentSearchProvider && e.enabled)
+          .where((e) => e.id == resolvedSearchProvider && e.enabled)
           .firstOrNull;
       final filters = currentSearchExtension?.searchBehavior?.filters;
       if (filters != null && filters.isNotEmpty) {
@@ -449,6 +453,153 @@ class _HomeTabState extends ConsumerState<HomeTab>
     ];
   }
 
+  Extension? _defaultSearchExtension(List<Extension> extensions) {
+    return extensions
+            .where(
+              (ext) =>
+                  ext.enabled &&
+                  ext.hasCustomSearch &&
+                  ext.searchBehavior?.primary == true,
+            )
+            .firstOrNull ??
+        extensions
+            .where((ext) => ext.enabled && ext.hasCustomSearch)
+            .firstOrNull;
+  }
+
+  String? _resolveSearchProvider(
+    String? explicitSearchProvider,
+    List<Extension> extensions,
+  ) {
+    final explicit = explicitSearchProvider?.trim();
+    if (explicit != null &&
+        explicit.isNotEmpty &&
+        (_builtInSearchProviders.contains(explicit) ||
+            extensions.any(
+              (ext) => ext.enabled && ext.hasCustomSearch && ext.id == explicit,
+            ))) {
+      return explicit;
+    }
+    return _defaultSearchExtension(extensions)?.id ?? 'tidal';
+  }
+
+  String? _sanitizeSearchFilterForProvider(
+    String? filter,
+    String? currentSearchProvider,
+    List<Extension> extensions,
+  ) {
+    if (filter == null || filter.isEmpty) {
+      return null;
+    }
+
+    final canonicalFilter = _canonicalSearchFilterId(filter);
+
+    if (currentSearchProvider == null ||
+        currentSearchProvider.isEmpty ||
+        _builtInSearchProviders.contains(currentSearchProvider)) {
+      switch (canonicalFilter) {
+        case 'track':
+        case 'artist':
+        case 'album':
+        case 'playlist':
+          return canonicalFilter;
+        default:
+          return null;
+      }
+    }
+
+    final extension = extensions
+        .where((e) => e.id == currentSearchProvider && e.enabled)
+        .firstOrNull;
+    final filters = extension?.searchBehavior?.filters;
+    if (filters == null || filters.isEmpty) {
+      return null;
+    }
+
+    final match = filters
+        .where(
+          (candidate) =>
+              _canonicalSearchFilterId(candidate.id) == canonicalFilter ||
+              (candidate.label != null &&
+                  _canonicalSearchFilterId(candidate.label!) ==
+                      canonicalFilter) ||
+              (candidate.icon != null &&
+                  _canonicalSearchFilterId(candidate.icon!) == canonicalFilter),
+        )
+        .firstOrNull;
+    return match?.id;
+  }
+
+  String _canonicalSearchFilterId(String value) {
+    final normalized = value.trim().toLowerCase().replaceAll(
+      RegExp(r'[^a-z0-9]+'),
+      '',
+    );
+    switch (normalized) {
+      case 'track':
+      case 'tracks':
+      case 'song':
+      case 'songs':
+      case 'music':
+        return 'track';
+      case 'artist':
+      case 'artists':
+        return 'artist';
+      case 'album':
+      case 'albums':
+        return 'album';
+      case 'playlist':
+      case 'playlists':
+        return 'playlist';
+      default:
+        return normalized;
+    }
+  }
+
+  String? _preferredSearchFilter(
+    String preferredSearchTab,
+    String? currentSearchProvider,
+    List<Extension> extensions,
+  ) {
+    final preferred = switch (preferredSearchTab) {
+      'track' => 'track',
+      'artist' => 'artist',
+      'album' => 'album',
+      _ => null,
+    };
+
+    return _sanitizeSearchFilterForProvider(
+      preferred,
+      currentSearchProvider,
+      extensions,
+    );
+  }
+
+  String _displaySearchFilterSelection(
+    String? selectedSearchFilter,
+    String preferredSearchTab,
+    String? currentSearchProvider,
+    List<Extension> extensions,
+  ) {
+    if (selectedSearchFilter == 'all') {
+      return 'all';
+    }
+    if (selectedSearchFilter != null && selectedSearchFilter.isNotEmpty) {
+      return _sanitizeSearchFilterForProvider(
+            selectedSearchFilter,
+            currentSearchProvider,
+            extensions,
+          ) ??
+          'all';
+    }
+    return _preferredSearchFilter(
+          preferredSearchTab,
+          currentSearchProvider,
+          extensions,
+        ) ??
+        'all';
+  }
+
   _SearchResultBuckets _getSearchResultBuckets(List<Track> tracks) {
     final cached = _searchBucketsCache;
     if (cached != null && identical(tracks, _searchBucketsSourceTracks)) {
@@ -530,7 +681,10 @@ class _HomeTabState extends ConsumerState<HomeTab>
   bool _isLiveSearchEnabled() {
     final settings = ref.read(settingsProvider);
     final extState = ref.read(extensionProvider);
-    final searchProvider = settings.searchProvider;
+    final searchProvider = _resolveSearchProvider(
+      settings.searchProvider,
+      extState.extensions,
+    );
 
     if (searchProvider == null || searchProvider.isEmpty) return false;
 
@@ -599,9 +753,32 @@ class _HomeTabState extends ConsumerState<HomeTab>
   Future<void> _performSearch(String query, {String? filterOverride}) async {
     final settings = ref.read(settingsProvider);
     final extState = ref.read(extensionProvider);
-    final searchProvider = settings.searchProvider;
-    final selectedFilter =
-        filterOverride ?? ref.read(trackProvider).selectedSearchFilter;
+    final searchProvider = _resolveSearchProvider(
+      settings.searchProvider,
+      extState.extensions,
+    );
+    final storedFilter = ref.read(trackProvider).selectedSearchFilter;
+    final selectedFilter = switch (filterOverride) {
+      'all' => null,
+      final explicit? => _sanitizeSearchFilterForProvider(
+        explicit,
+        searchProvider,
+        extState.extensions,
+      ),
+      null => switch (storedFilter) {
+        'all' => null,
+        final stored? => _sanitizeSearchFilterForProvider(
+          stored,
+          searchProvider,
+          extState.extensions,
+        ),
+        null => _preferredSearchFilter(
+          settings.defaultSearchTab,
+          searchProvider,
+          extState.extensions,
+        ),
+      },
+    };
 
     final searchKey =
         '${searchProvider ?? 'default'}:$query:${selectedFilter ?? 'all'}';
@@ -627,7 +804,12 @@ class _HomeTabState extends ConsumerState<HomeTab>
       }
       await ref
           .read(trackProvider.notifier)
-          .customSearch(searchProvider, query, options: options);
+          .customSearch(
+            searchProvider,
+            query,
+            options: options,
+            selectedFilter: selectedFilter,
+          );
     } else if (isBuiltInProvider) {
       await ref
           .read(trackProvider.notifier)
@@ -1062,6 +1244,9 @@ class _HomeTabState extends ConsumerState<HomeTab>
     final hasSearchedBefore = ref.watch(
       settingsProvider.select((s) => s.hasSearchedBefore),
     );
+    final defaultSearchTab = ref.watch(
+      settingsProvider.select((s) => s.defaultSearchTab),
+    );
 
     final hasExploreContent = ref.watch(
       exploreProvider.select((s) => s.sections.isNotEmpty),
@@ -1103,6 +1288,29 @@ class _HomeTabState extends ConsumerState<HomeTab>
         (hasHomeFeedExtension || hasExploreContent) &&
         hasExploreContent;
 
+    ref.listen<String>(settingsProvider.select((s) => s.defaultSearchTab), (
+      previous,
+      next,
+    ) {
+      if (previous == next) return;
+      final selectedSearchFilter = ref.read(
+        trackProvider.select((s) => s.selectedSearchFilter),
+      );
+      if (selectedSearchFilter != null && selectedSearchFilter.isNotEmpty) {
+        return;
+      }
+
+      final text = _urlController.text.trim();
+      if (text.isEmpty || text.length < _minLiveSearchChars) return;
+      if (text.startsWith('http') || text.startsWith('spotify:')) return;
+
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (!mounted) return;
+        _lastSearchQuery = null;
+        _performSearch(text);
+      });
+    });
+
     if (hasActualResults &&
         isShowingRecentAccess &&
         hasSearchInput &&
@@ -1246,7 +1454,12 @@ class _HomeTabState extends ConsumerState<HomeTab>
                     return SliverToBoxAdapter(
                       child: _buildSearchFilterBar(
                         searchFilters,
-                        selectedSearchFilter,
+                        _displaySearchFilterSelection(
+                          selectedSearchFilter,
+                          defaultSearchTab,
+                          currentSearchProvider,
+                          extensions,
+                        ),
                         colorScheme,
                       ),
                     );
@@ -2092,17 +2305,25 @@ class _HomeTabState extends ConsumerState<HomeTab>
     );
   }
 
+  bool _isEnabledMetadataExtension(String? providerId) {
+    final normalized = providerId?.trim();
+    if (normalized == null || normalized.isEmpty) return false;
+
+    return ref
+        .read(extensionProvider)
+        .extensions
+        .any(
+          (ext) =>
+              ext.enabled && ext.hasMetadataProvider && ext.id == normalized,
+        );
+  }
+
   void _navigateToRecentItem(RecentAccessItem item) {
     _searchFocusNode.unfocus();
 
     switch (item.type) {
       case RecentAccessType.artist:
-        if (item.providerId != null &&
-            item.providerId!.isNotEmpty &&
-            item.providerId != 'deezer' &&
-            item.providerId != 'spotify' &&
-            item.providerId != 'tidal' &&
-            item.providerId != 'qobuz') {
+        if (_isEnabledMetadataExtension(item.providerId)) {
           Navigator.push(
             context,
             MaterialPageRoute<void>(
@@ -2139,12 +2360,7 @@ class _HomeTabState extends ConsumerState<HomeTab>
               ),
             ),
           );
-        } else if (item.providerId != null &&
-            item.providerId!.isNotEmpty &&
-            item.providerId != 'deezer' &&
-            item.providerId != 'spotify' &&
-            item.providerId != 'tidal' &&
-            item.providerId != 'qobuz') {
+        } else if (_isEnabledMetadataExtension(item.providerId)) {
           Navigator.push(
             context,
             MaterialPageRoute<void>(
@@ -2189,12 +2405,7 @@ class _HomeTabState extends ConsumerState<HomeTab>
           return;
         }
 
-        if (item.providerId != null &&
-            item.providerId!.isNotEmpty &&
-            item.providerId != 'deezer' &&
-            item.providerId != 'spotify' &&
-            item.providerId != 'tidal' &&
-            item.providerId != 'qobuz') {
+        if (_isEnabledMetadataExtension(item.providerId)) {
           Navigator.push(
             context,
             MaterialPageRoute<void>(
@@ -3111,8 +3322,11 @@ class _HomeTabState extends ConsumerState<HomeTab>
 
   String _getSearchHint() {
     final settings = ref.read(settingsProvider);
-    final searchProvider = settings.searchProvider;
     final extState = ref.read(extensionProvider);
+    final searchProvider = _resolveSearchProvider(
+      settings.searchProvider,
+      extState.extensions,
+    );
 
     if (!extState.isInitialized) {
       return 'Paste supported URL or search...';
@@ -3154,10 +3368,10 @@ class _HomeTabState extends ConsumerState<HomeTab>
               padding: const EdgeInsets.only(right: 8),
               child: FilterChip(
                 label: Text(context.l10n.historyFilterAll),
-                selected: selectedFilter == null,
+                selected: selectedFilter == 'all',
                 onSelected: (_) {
-                  ref.read(trackProvider.notifier).setSearchFilter(null);
-                  _triggerSearchWithFilter(null);
+                  ref.read(trackProvider.notifier).setSearchFilter('all');
+                  _triggerSearchWithFilter('all');
                 },
                 showCheckmark: false,
               ),
@@ -3313,9 +3527,23 @@ class _SearchProviderDropdown extends ConsumerWidget {
 
   const _SearchProviderDropdown({this.onProviderChanged});
 
+  Extension? _defaultSearchExtension(List<Extension> extensions) {
+    return extensions
+            .where(
+              (ext) =>
+                  ext.enabled &&
+                  ext.hasCustomSearch &&
+                  ext.searchBehavior?.primary == true,
+            )
+            .firstOrNull ??
+        extensions
+            .where((ext) => ext.enabled && ext.hasCustomSearch)
+            .firstOrNull;
+  }
+
   @override
   Widget build(BuildContext context, WidgetRef ref) {
-    final currentProvider = ref.watch(
+    final rawCurrentProvider = ref.watch(
       settingsProvider.select((s) => s.searchProvider),
     );
     final extensions = ref.watch(extensionProvider.select((s) => s.extensions));
@@ -3324,6 +3552,19 @@ class _SearchProviderDropdown extends ConsumerWidget {
     final searchProviders = extensions
         .where((ext) => ext.enabled && ext.hasCustomSearch)
         .toList();
+    final primarySearchExtension = _defaultSearchExtension(searchProviders);
+    final defaultProviderTarget =
+        primarySearchExtension?.displayName ?? 'Tidal';
+    final defaultProviderLabel =
+        '${context.l10n.extensionsHomeFeedAuto} ($defaultProviderTarget)';
+    final defaultProviderIconPath = primarySearchExtension?.iconPath;
+    final currentProvider =
+        rawCurrentProvider != null &&
+            rawCurrentProvider.isNotEmpty &&
+            ({'tidal', 'qobuz'}.contains(rawCurrentProvider) ||
+                searchProviders.any((e) => e.id == rawCurrentProvider))
+        ? rawCurrentProvider
+        : null;
 
     Extension? currentExt;
     if (currentProvider != null && currentProvider.isNotEmpty) {
@@ -3343,6 +3584,19 @@ class _SearchProviderDropdown extends ConsumerWidget {
       if (currentExt.searchBehavior?.icon != null) {
         displayIcon = _getIconFromName(currentExt.searchBehavior!.icon!);
       }
+    } else if (primarySearchExtension?.searchBehavior?.icon != null) {
+      displayIcon = _getIconFromName(
+        primarySearchExtension!.searchBehavior!.icon!,
+      );
+      iconPath = defaultProviderIconPath;
+    } else if (defaultProviderIconPath != null &&
+        defaultProviderIconPath.isNotEmpty) {
+      iconPath = defaultProviderIconPath;
+      if (primarySearchExtension?.searchBehavior?.icon != null) {
+        displayIcon = _getIconFromName(
+          primarySearchExtension!.searchBehavior!.icon!,
+        );
+      }
     } else if (isBuiltInProvider) {
       displayIcon = Icons.music_note;
     }
@@ -3397,7 +3651,7 @@ class _SearchProviderDropdown extends ConsumerWidget {
                 const SizedBox(width: 12),
                 Expanded(
                   child: Text(
-                    'Deezer',
+                    defaultProviderLabel,
                     style: TextStyle(
                       fontWeight:
                           currentProvider == null || currentProvider.isEmpty

lib/screens/main_shell.dart

@@ -7,7 +7,6 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
-import 'package:spotiflac_android/providers/extension_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/providers/store_provider.dart';
 import 'package:spotiflac_android/providers/track_provider.dart';
@@ -94,20 +93,6 @@ class _MainShellState extends ConsumerState<MainShell>
   }
 
   Future<void> _handleSharedUrl(String url) async {
-    // Wait for extensions to be initialized before handling URL
-    final extState = ref.read(extensionProvider);
-    if (!extState.isInitialized) {
-      _log.d('Waiting for extensions to initialize before handling URL...');
-      for (int i = 0; i < 50; i++) {
-        await Future<void>.delayed(const Duration(milliseconds: 100));
-        if (!mounted) return;
-        if (ref.read(extensionProvider).isInitialized) {
-          _log.d('Extensions initialized, proceeding with URL handling');
-          break;
-        }
-      }
-    }
-
     if (!mounted) return;
 
     Navigator.of(context).popUntil((route) => route.isFirst);

lib/screens/queue_tab.dart

@@ -4333,6 +4333,40 @@ class _QueueTabState extends ConsumerState<QueueTab> {
             ),
           ),
 
+        if (filterMode == 'all' &&
+            totalTrackCount == 0 &&
+            !showFilteringIndicator &&
+            (_activeFilterCount > 0 || unifiedItems.isNotEmpty))
+          SliverToBoxAdapter(
+            child: Padding(
+              padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
+              child: Row(
+                children: [
+                  const Spacer(),
+                  if (!_isSelectionMode)
+                    _buildFilterButton(context, unifiedItems),
+                ],
+              ),
+            ),
+          ),
+
+        if (filterMode == 'singles' &&
+            totalTrackCount == 0 &&
+            !showFilteringIndicator &&
+            (_activeFilterCount > 0 || unifiedItems.isNotEmpty))
+          SliverToBoxAdapter(
+            child: Padding(
+              padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
+              child: Row(
+                children: [
+                  const Spacer(),
+                  if (!_isSelectionMode)
+                    _buildFilterButton(context, unifiedItems),
+                ],
+              ),
+            ),
+          ),
+
         if (historyItems.isNotEmpty && hasQueueItems)
           SliverToBoxAdapter(
             child: Padding(

lib/screens/repo_tab.dart

@@ -789,13 +789,6 @@ class _ExtensionItem extends StatelessWidget {
                           ),
                         ],
                       ),
-                      const SizedBox(height: 2),
-                      Text(
-                        'by ${extension.author}',
-                        style: Theme.of(context).textTheme.bodySmall?.copyWith(
-                          color: colorScheme.onSurfaceVariant,
-                        ),
-                      ),
                       if (extension.requiresNewerApp) ...[
                         const SizedBox(height: 4),
                         Container(

lib/screens/settings/about_page.dart

@@ -182,6 +182,13 @@ class AboutPage extends StatelessWidget {
                     onTap: () => _launchUrl(AppInfo.originalGithubUrl),
                     showDivider: true,
                   ),
+                  _AboutSettingsItem(
+                    icon: Icons.campaign_outlined,
+                    title: context.l10n.aboutKeepAndroidOpen,
+                    subtitle: 'keepandroidopen.org',
+                    onTap: () => _launchUrl('https://keepandroidopen.org/'),
+                    showDivider: true,
+                  ),
                   _AboutSettingsItem(
                     icon: Icons.bug_report_outlined,
                     title: context.l10n.aboutReportIssue,

lib/screens/settings/donate_page.dart

@@ -164,7 +164,15 @@ class _RecentDonorsCard extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final isDark = Theme.of(context).brightness == Brightness.dark;
-    const donorNames = <String>['R4ND0MIZ3D', 'Isra', 'bigJr48'];
+    const donorNames = <String>[
+      'Ldav',
+      'Nico',
+      'Feuerstern',
+      'R4ND0MIZ3D',
+      'Isra',
+      'bigJr48',
+      'Mick',
+    ];
 
     // Match SettingsGroup color logic
     final cardColor = isDark

lib/screens/settings/extension_detail_page.dart

@@ -8,6 +8,7 @@ import 'package:spotiflac_android/providers/store_provider.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/utils/app_bar_layout.dart';
 import 'package:spotiflac_android/widgets/settings_group.dart';
+import 'package:url_launcher/url_launcher.dart';
 
 class ExtensionDetailPage extends ConsumerStatefulWidget {
   final String extensionId;
@@ -49,7 +50,6 @@ class _ExtensionDetailPageState extends ConsumerState<ExtensionDetailPage> {
         name: '',
         displayName: 'Unknown',
         version: '0.0.0',
-        author: 'Unknown',
         description: '',
         enabled: false,
         status: 'error',
@@ -205,10 +205,6 @@ class _ExtensionDetailPageState extends ConsumerState<ExtensionDetailPage> {
                         ),
                       ],
                       const SizedBox(height: 16),
-                      _InfoRow(
-                        label: context.l10n.extensionAuthor,
-                        value: extension.author,
-                      ),
                       _InfoRow(
                         label: context.l10n.extensionId,
                         value: extension.id,
@@ -404,6 +400,7 @@ class _ExtensionDetailPageState extends ConsumerState<ExtensionDetailPage> {
                         onChanged: (value) =>
                             _updateSetting(setting.key, value),
                         extensionId: widget.extensionId,
+                        onActionPayload: _handleExtensionActionPayload,
                       );
                     }).toList(),
                   ),
@@ -445,6 +442,27 @@ class _ExtensionDetailPageState extends ConsumerState<ExtensionDetailPage> {
         .setExtensionSettings(widget.extensionId, _settings);
   }
 
+  /// Extensions may return `setting_updates` from button actions (e.g. OAuth URL field).
+  Future<void> _handleExtensionActionPayload(
+    Map<String, dynamic> payload,
+  ) async {
+    final raw = payload['setting_updates'];
+    if (raw is! Map) return;
+    final partial = <String, dynamic>{};
+    for (final entry in raw.entries) {
+      partial[entry.key.toString()] = entry.value;
+    }
+    if (partial.isEmpty) return;
+    final merged = Map<String, dynamic>.from(_settings);
+    merged.addAll(partial);
+    await ref
+        .read(extensionProvider.notifier)
+        .setExtensionSettings(widget.extensionId, merged);
+    if (mounted) {
+      setState(() => _settings = merged);
+    }
+  }
+
   Future<void> _confirmRemove(BuildContext context) async {
     final colorScheme = Theme.of(context).colorScheme;
     final confirmed = await showDialog<bool>(
@@ -478,6 +496,41 @@ class _ExtensionDetailPageState extends ConsumerState<ExtensionDetailPage> {
   }
 }
 
+/// Long OAuth URLs: selectable text so users can copy without relying on snackbars.
+class _OauthLoginLinkPreview extends StatelessWidget {
+  final String? value;
+  final ColorScheme colorScheme;
+
+  const _OauthLoginLinkPreview({
+    required this.value,
+    required this.colorScheme,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final text = value?.trim() ?? '';
+    if (text.isEmpty) {
+      return Text(
+        'Tap Connect to Spotify to fill this field.',
+        style: Theme.of(context).textTheme.bodySmall?.copyWith(
+          color: colorScheme.onSurfaceVariant,
+          fontStyle: FontStyle.italic,
+        ),
+      );
+    }
+    return SelectionArea(
+      child: Text(
+        text,
+        style: Theme.of(context).textTheme.bodySmall?.copyWith(
+          color: colorScheme.primary,
+          fontFamily: 'monospace',
+          fontSize: 11,
+        ),
+      ),
+    );
+  }
+}
+
 class _InfoRow extends StatelessWidget {
   final String label;
   final String value;
@@ -645,12 +698,14 @@ class _SettingItem extends StatefulWidget {
   final bool showDivider;
   final ValueChanged<dynamic> onChanged;
   final String extensionId;
+  final Future<void> Function(Map<String, dynamic> payload)? onActionPayload;
 
   const _SettingItem({
     required this.setting,
     required this.value,
     required this.onChanged,
     required this.extensionId,
+    this.onActionPayload,
     this.showDivider = true,
   });
 
@@ -772,11 +827,17 @@ class _SettingItemState extends State<_SettingItem> {
                       if (widget.setting.type == 'string' ||
                           widget.setting.type == 'number') ...[
                         const SizedBox(height: 4),
-                        Text(
-                          widget.value?.toString() ?? 'Not set',
-                          style: Theme.of(context).textTheme.bodySmall
-                              ?.copyWith(color: colorScheme.primary),
-                        ),
+                        if (widget.setting.key == 'oauth_login_url')
+                          _OauthLoginLinkPreview(
+                            value: widget.value?.toString(),
+                            colorScheme: colorScheme,
+                          )
+                        else
+                          Text(
+                            widget.value?.toString() ?? 'Not set',
+                            style: Theme.of(context).textTheme.bodySmall
+                                ?.copyWith(color: colorScheme.primary),
+                          ),
                       ],
                     ],
                   ),
@@ -815,15 +876,45 @@ class _SettingItemState extends State<_SettingItem> {
       );
 
       if (context.mounted) {
-        final success = result['success'] as bool? ?? false;
+        // Go may return either a flat map or { success, result: { ... } }.
+        Map<String, dynamic> payload = result;
+        final nested = result['result'];
+        if (nested is Map) {
+          payload = Map<String, dynamic>.from(nested);
+        }
+
+        final success = payload['success'] as bool? ?? false;
         if (!success) {
-          final error = result['error'] as String? ?? 'Action failed';
+          final error =
+              payload['error'] as String? ??
+              result['error'] as String? ??
+              'Action failed';
           ScaffoldMessenger.of(
             context,
           ).showSnackBar(SnackBar(content: Text(error)));
         } else {
-          final message = result['message'] as String?;
-          if (message != null) {
+          if (widget.onActionPayload != null) {
+            await widget.onActionPayload!(payload);
+          }
+          final openAuth = payload['open_auth_url'] as String?;
+          if (openAuth != null && openAuth.isNotEmpty) {
+            final uri = Uri.parse(openAuth);
+            final launched = await launchUrl(
+              uri,
+              mode: LaunchMode.externalApplication,
+            );
+            if (!launched && context.mounted) {
+              ScaffoldMessenger.of(context).showSnackBar(
+                SnackBar(
+                  content: Text(
+                    context.l10n.snackbarError('Could not open browser'),
+                  ),
+                ),
+              );
+            }
+          }
+          final message = payload['message'] as String?;
+          if (message != null && message.isNotEmpty && context.mounted) {
             ScaffoldMessenger.of(
               context,
             ).showSnackBar(SnackBar(content: Text(message)));

lib/screens/settings/extensions_page.dart

@@ -425,7 +425,7 @@ class _ExtensionItem extends StatelessWidget {
                         hasError
                             ? extension.errorMessage ??
                                   context.l10n.extensionsErrorLoading
-                            : 'v${extension.version} ${context.l10n.extensionsAuthor(extension.author)}',
+                            : 'v${extension.version}',
                         style: Theme.of(context).textTheme.bodySmall?.copyWith(
                           color: hasError
                               ? colorScheme.error

lib/screens/settings/metadata_provider_priority_page.dart

@@ -225,8 +225,8 @@ class _MetadataProviderItem extends StatelessWidget {
         return _MetadataProviderInfo(
           name: 'Deezer',
           icon: Icons.album,
-          description: context.l10n.metadataNoRateLimits,
-          isBuiltIn: true,
+          description: context.l10n.providerExtension,
+          isBuiltIn: false,
         );
       case 'qobuz':
         return _MetadataProviderInfo(

lib/screens/settings/options_settings_page.dart

@@ -70,7 +70,12 @@ class OptionsSettingsPage extends ConsumerWidget {
               ),
             ),
             SliverToBoxAdapter(
-              child: SettingsGroup(children: [const _MetadataSourceSelector()]),
+              child: SettingsGroup(
+                children: const [
+                  _MetadataSourceSelector(),
+                  _DefaultSearchTabSelector(),
+                ],
+              ),
             ),
 
             SliverToBoxAdapter(
@@ -714,13 +719,41 @@ class _MetadataSourceSelector extends ConsumerWidget {
 
   static const _builtInProviders = {'tidal': 'Tidal', 'qobuz': 'Qobuz'};
 
+  Extension? _defaultSearchExtension(List<Extension> extensions) {
+    return extensions
+            .where(
+              (ext) =>
+                  ext.enabled &&
+                  ext.hasCustomSearch &&
+                  ext.searchBehavior?.primary == true,
+            )
+            .firstOrNull ??
+        extensions
+            .where((ext) => ext.enabled && ext.hasCustomSearch)
+            .firstOrNull;
+  }
+
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final colorScheme = Theme.of(context).colorScheme;
     final settings = ref.watch(settingsProvider);
     final extState = ref.watch(extensionProvider);
 
-    final searchProvider = settings.searchProvider ?? '';
+    final rawSearchProvider = settings.searchProvider?.trim() ?? '';
+    final isValidBuiltIn = _builtInProviders.containsKey(rawSearchProvider);
+    final primarySearchExtension = _defaultSearchExtension(extState.extensions);
+    final defaultProviderTarget =
+        primarySearchExtension?.displayName ?? 'Tidal';
+    final defaultProviderLabel =
+        '${context.l10n.extensionsHomeFeedAuto} ($defaultProviderTarget)';
+    final searchProvider =
+        isValidBuiltIn ||
+            extState.extensions.any(
+              (e) =>
+                  e.enabled && e.hasCustomSearch && e.id == rawSearchProvider,
+            )
+        ? rawSearchProvider
+        : '';
     final isBuiltIn = _builtInProviders.containsKey(searchProvider);
 
     Extension? activeExtension;
@@ -765,37 +798,45 @@ class _MetadataSourceSelector extends ConsumerWidget {
           const SizedBox(height: 16),
           Row(
             children: [
-              _SourceChip(
-                icon: Icons.graphic_eq,
-                label: 'Deezer',
-                isSelected: searchProvider.isEmpty,
-                onTap: () {
-                  if (hasNonDefaultProvider) {
-                    ref.read(settingsProvider.notifier).setSearchProvider(null);
-                  }
-                },
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.graphic_eq,
+                  label: defaultProviderLabel,
+                  isSelected: searchProvider.isEmpty,
+                  onTap: () {
+                    if (hasNonDefaultProvider) {
+                      ref
+                          .read(settingsProvider.notifier)
+                          .setSearchProvider(null);
+                    }
+                  },
+                ),
               ),
               const SizedBox(width: 8),
-              _SourceChip(
-                icon: Icons.waves,
-                label: 'Tidal',
-                isSelected: searchProvider == 'tidal',
-                onTap: () {
-                  ref
-                      .read(settingsProvider.notifier)
-                      .setSearchProvider('tidal');
-                },
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.waves,
+                  label: 'Tidal',
+                  isSelected: searchProvider == 'tidal',
+                  onTap: () {
+                    ref
+                        .read(settingsProvider.notifier)
+                        .setSearchProvider('tidal');
+                  },
+                ),
               ),
               const SizedBox(width: 8),
-              _SourceChip(
-                icon: Icons.album,
-                label: 'Qobuz',
-                isSelected: searchProvider == 'qobuz',
-                onTap: () {
-                  ref
-                      .read(settingsProvider.notifier)
-                      .setSearchProvider('qobuz');
-                },
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.album,
+                  label: 'Qobuz',
+                  isSelected: searchProvider == 'qobuz',
+                  onTap: () {
+                    ref
+                        .read(settingsProvider.notifier)
+                        .setSearchProvider('qobuz');
+                  },
+                ),
               ),
             ],
           ),
@@ -811,7 +852,7 @@ class _MetadataSourceSelector extends ConsumerWidget {
                 const SizedBox(width: 8),
                 Expanded(
                   child: Text(
-                    'Tap Deezer to switch back from extension',
+                    'Tap $defaultProviderLabel to switch back from extension',
                     style: Theme.of(context).textTheme.bodySmall?.copyWith(
                       color: colorScheme.onSurfaceVariant,
                     ),
@@ -826,6 +867,88 @@ class _MetadataSourceSelector extends ConsumerWidget {
   }
 }
 
+class _DefaultSearchTabSelector extends ConsumerWidget {
+  const _DefaultSearchTabSelector();
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final colorScheme = Theme.of(context).colorScheme;
+    final selectedTab = ref.watch(
+      settingsProvider.select((s) => s.defaultSearchTab),
+    );
+
+    return Padding(
+      padding: const EdgeInsets.fromLTRB(16, 0, 16, 16),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            context.l10n.optionsDefaultSearchTab,
+            style: Theme.of(
+              context,
+            ).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w500),
+          ),
+          const SizedBox(height: 4),
+          Text(
+            context.l10n.optionsDefaultSearchTabSubtitle,
+            style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+              color: colorScheme.onSurfaceVariant,
+            ),
+          ),
+          const SizedBox(height: 16),
+          Row(
+            children: [
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.dashboard_outlined,
+                  label: context.l10n.historyFilterAll,
+                  isSelected: selectedTab == 'all',
+                  onTap: () => ref
+                      .read(settingsProvider.notifier)
+                      .setDefaultSearchTab('all'),
+                ),
+              ),
+              const SizedBox(width: 8),
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.music_note,
+                  label: context.l10n.searchSongs,
+                  isSelected: selectedTab == 'track',
+                  onTap: () => ref
+                      .read(settingsProvider.notifier)
+                      .setDefaultSearchTab('track'),
+                ),
+              ),
+              const SizedBox(width: 8),
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.person,
+                  label: context.l10n.searchArtists,
+                  isSelected: selectedTab == 'artist',
+                  onTap: () => ref
+                      .read(settingsProvider.notifier)
+                      .setDefaultSearchTab('artist'),
+                ),
+              ),
+              const SizedBox(width: 8),
+              Expanded(
+                child: _SourceChip(
+                  icon: Icons.album,
+                  label: context.l10n.searchAlbums,
+                  isSelected: selectedTab == 'album',
+                  onTap: () => ref
+                      .read(settingsProvider.notifier)
+                      .setDefaultSearchTab('album'),
+                ),
+              ),
+            ],
+          ),
+        ],
+      ),
+    );
+  }
+}
+
 class _SourceChip extends StatelessWidget {
   final IconData icon;
   final String label;
@@ -851,39 +974,36 @@ class _SourceChip extends StatelessWidget {
           )
         : colorScheme.surfaceContainerHigh;
 
-    return Expanded(
-      child: Material(
-        color: isSelected ? colorScheme.primaryContainer : unselectedColor,
+    return Material(
+      color: isSelected ? colorScheme.primaryContainer : unselectedColor,
+      borderRadius: BorderRadius.circular(12),
+      child: InkWell(
+        onTap: onTap,
         borderRadius: BorderRadius.circular(12),
-        child: InkWell(
-          onTap: onTap,
-          borderRadius: BorderRadius.circular(12),
-          child: Padding(
-            padding: const EdgeInsets.symmetric(vertical: 14),
-            child: Column(
-              children: [
-                Icon(
-                  icon,
-                  size: 28,
+        child: Padding(
+          padding: const EdgeInsets.symmetric(vertical: 14, horizontal: 18),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Icon(
+                icon,
+                size: 28,
+                color: isSelected
+                    ? colorScheme.onPrimaryContainer
+                    : colorScheme.onSurfaceVariant,
+              ),
+              const SizedBox(height: 6),
+              Text(
+                label,
+                style: TextStyle(
+                  fontSize: 12,
+                  fontWeight: isSelected ? FontWeight.w600 : FontWeight.normal,
                   color: isSelected
                       ? colorScheme.onPrimaryContainer
                       : colorScheme.onSurfaceVariant,
                 ),
-                const SizedBox(height: 6),
-                Text(
-                  label,
-                  style: TextStyle(
-                    fontSize: 12,
-                    fontWeight: isSelected
-                        ? FontWeight.w600
-                        : FontWeight.normal,
-                    color: isSelected
-                        ? colorScheme.onPrimaryContainer
-                        : colorScheme.onSurfaceVariant,
-                  ),
-                ),
-              ],
-            ),
+              ),
+            ],
           ),
         ),
       ),

lib/screens/setup_screen.dart

@@ -10,6 +10,9 @@ import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/utils/file_access.dart';
+import 'package:spotiflac_android/utils/logger.dart';
+
+final _log = AppLogger('SetupScreen');
 
 class SetupScreen extends ConsumerStatefulWidget {
   const SetupScreen({super.key});
@@ -233,7 +236,21 @@ class _SetupScreenState extends ConsumerState<SetupScreen> {
       if (Platform.isIOS) {
         await _showIOSDirectoryOptions();
       } else if (Platform.isAndroid) {
-        final result = await PlatformBridge.pickSafTree();
+        Map<String, dynamic>? result;
+        try {
+          result = await PlatformBridge.pickSafTree();
+        } catch (e) {
+          _log.w('Failed to open Android SAF picker: $e');
+          if (mounted) {
+            ScaffoldMessenger.of(context).showSnackBar(
+              SnackBar(
+                content: Text(
+                  context.l10n.snackbarCannotOpenFile(e.toString()),
+                ),
+              ),
+            );
+          }
+        }
         if (result != null) {
           final treeUri = result['tree_uri'] as String? ?? '';
           final displayName = result['display_name'] as String? ?? '';

lib/screens/store/extension_details_screen.dart

@@ -171,12 +171,6 @@ class _ExtensionDetailsScreenState
                                   color: colorScheme.onSurface,
                                 ),
                           ),
-                          const SizedBox(height: 4),
-                          Text(
-                            context.l10n.extensionsAuthor(ext.author),
-                            style: Theme.of(context).textTheme.bodyLarge
-                                ?.copyWith(color: colorScheme.onSurfaceVariant),
-                          ),
                         ],
                       ),
                     ),

lib/screens/track_metadata_screen.dart

@@ -4270,8 +4270,12 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
       'copyright': val('copyright', copyright),
       'composer': val('composer', composer),
       'comment': fileMetadata?['comment']?.toString() ?? '',
+      'lyrics': fileMetadata?['lyrics']?.toString() ?? '',
     };
 
+    final initialDurationSeconds =
+        _readPositiveInt(fileMetadata?['duration']) ?? duration ?? 0;
+
     if (!context.mounted) return;
 
     final saved = await showModalBottomSheet<bool>(
@@ -4287,6 +4291,9 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
         initialValues: initialValues,
         filePath: cleanFilePath,
         sourceTrackId: _spotifyId,
+        durationMs: initialDurationSeconds > 0
+            ? initialDurationSeconds * 1000
+            : 0,
         artistTagMode: ref.read(settingsProvider).artistTagMode,
       ),
     );
@@ -4297,7 +4304,24 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
       );
       try {
         final refreshed = await PlatformBridge.readFileMetadata(cleanFilePath);
-        setState(() => _editedMetadata = refreshed);
+        final refreshedLyrics = refreshed['lyrics']?.toString().trim() ?? '';
+        setState(() {
+          _editedMetadata = refreshed;
+          _lyricsError = null;
+          _isInstrumental = false;
+          _embeddedLyricsChecked = true;
+          if (refreshedLyrics.isNotEmpty) {
+            _lyrics = _cleanLrcForDisplay(refreshedLyrics);
+            _rawLyrics = refreshedLyrics;
+            _lyricsSource = 'Embedded';
+            _lyricsEmbedded = true;
+          } else {
+            _lyrics = null;
+            _rawLyrics = null;
+            _lyricsSource = null;
+            _lyricsEmbedded = false;
+          }
+        });
       } catch (_) {
         setState(() {});
       }
@@ -4514,6 +4538,7 @@ class _EditMetadataSheet extends StatefulWidget {
   final Map<String, String> initialValues;
   final String filePath;
   final String? sourceTrackId;
+  final int durationMs;
   final String artistTagMode;
 
   const _EditMetadataSheet({
@@ -4521,6 +4546,7 @@ class _EditMetadataSheet extends StatefulWidget {
     required this.initialValues,
     required this.filePath,
     this.sourceTrackId,
+    required this.durationMs,
     required this.artistTagMode,
   });
 
@@ -4560,6 +4586,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
     'total_discs': 'total_discs',
     'genre': 'genre',
     'isrc': 'isrc',
+    'lyrics': 'lyrics',
     'label': 'label',
     'copyright': 'copyright',
     'composer': 'composer',
@@ -4577,6 +4604,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
   late final TextEditingController _discTotalCtrl;
   late final TextEditingController _genreCtrl;
   late final TextEditingController _isrcCtrl;
+  late final TextEditingController _lyricsCtrl;
   late final TextEditingController _labelCtrl;
   late final TextEditingController _copyrightCtrl;
   late final TextEditingController _composerCtrl;
@@ -4772,6 +4800,8 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
         return l10n.editMetadataFieldGenre;
       case 'isrc':
         return l10n.editMetadataFieldIsrc;
+      case 'lyrics':
+        return l10n.trackLyrics;
       case 'label':
         return l10n.editMetadataFieldLabel;
       case 'copyright':
@@ -4809,6 +4839,8 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
         return _genreCtrl;
       case 'isrc':
         return _isrcCtrl;
+      case 'lyrics':
+        return _lyricsCtrl;
       case 'label':
         return _labelCtrl;
       case 'copyright':
@@ -5107,19 +5139,23 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       final artist = _artistCtrl.text.trim();
       final album = _albumCtrl.text.trim();
       final currentIsrc = _isrcCtrl.text.trim().toUpperCase();
+      final shouldFetchLyrics = _autoFillFields.contains('lyrics');
+      final needsTrackLookup = _autoFillFields.any((key) => key != 'lyrics');
       Map<String, dynamic>? best;
       String? deezerId;
 
-      try {
-        final resolved = await _resolveAutoFillTrackFromIdentifiers(
-          currentIsrc,
-        );
-        if (resolved != null) {
-          best = resolved.track;
-          deezerId = resolved.deezerId;
+      if (needsTrackLookup) {
+        try {
+          final resolved = await _resolveAutoFillTrackFromIdentifiers(
+            currentIsrc,
+          );
+          if (resolved != null) {
+            best = resolved.track;
+            deezerId = resolved.deezerId;
+          }
+        } catch (e) {
+          _log.w('Identifier-first autofill lookup failed: $e');
         }
-      } catch (e) {
-        _log.w('Identifier-first autofill lookup failed: $e');
       }
 
       final queryParts = <String>[];
@@ -5127,7 +5163,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       if (artist.isNotEmpty) queryParts.add(artist);
       if (queryParts.isEmpty && album.isNotEmpty) queryParts.add(album);
 
-      if (best == null && queryParts.isEmpty) {
+      if (needsTrackLookup && best == null && queryParts.isEmpty) {
         if (mounted) {
           ScaffoldMessenger.of(context).showSnackBar(
             SnackBar(content: Text(context.l10n.editMetadataAutoFillNoResults)),
@@ -5140,7 +5176,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       final normalizedArtist = _normalizeMetadataText(artist);
       final normalizedAlbum = _normalizeMetadataText(album);
 
-      if (best == null) {
+      if (needsTrackLookup && best == null) {
         final query = queryParts.join(' ');
         final results = await PlatformBridge.searchTracksWithMetadataProviders(
           query,
@@ -5175,39 +5211,47 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       }
 
       final selectedBest = best;
-      if (selectedBest == null) {
+      if (needsTrackLookup && selectedBest == null) {
         throw StateError('No metadata match resolved for auto-fill');
       }
 
-      final enriched = <String, String>{
-        'title': (selectedBest['name'] ?? '').toString(),
-        'artist': (selectedBest['artists'] ?? selectedBest['artist'] ?? '')
-            .toString(),
-        'album': (selectedBest['album_name'] ?? selectedBest['album'] ?? '')
-            .toString(),
-        'album_artist': (selectedBest['album_artist'] ?? '').toString(),
-        'date': (selectedBest['release_date'] ?? '').toString(),
-        'track_number': (selectedBest['track_number'] ?? '').toString(),
-        'total_tracks': (selectedBest['total_tracks'] ?? '').toString(),
-        'disc_number': (selectedBest['disc_number'] ?? '').toString(),
-        'total_discs': (selectedBest['total_discs'] ?? '').toString(),
-        'isrc': (selectedBest['isrc'] ?? '').toString(),
-        'composer': (selectedBest['composer'] ?? '').toString(),
-      };
-      _mergeOnlineTrackData(enriched, selectedBest);
+      final enriched = <String, String>{};
+      if (selectedBest != null) {
+        enriched.addAll(<String, String>{
+          'title': (selectedBest['name'] ?? '').toString(),
+          'artist': (selectedBest['artists'] ?? selectedBest['artist'] ?? '')
+              .toString(),
+          'album': (selectedBest['album_name'] ?? selectedBest['album'] ?? '')
+              .toString(),
+          'album_artist': (selectedBest['album_artist'] ?? '').toString(),
+          'date': (selectedBest['release_date'] ?? '').toString(),
+          'track_number': (selectedBest['track_number'] ?? '').toString(),
+          'total_tracks': (selectedBest['total_tracks'] ?? '').toString(),
+          'disc_number': (selectedBest['disc_number'] ?? '').toString(),
+          'total_discs': (selectedBest['total_discs'] ?? '').toString(),
+          'isrc': (selectedBest['isrc'] ?? '').toString(),
+          'composer': (selectedBest['composer'] ?? '').toString(),
+        });
+        _mergeOnlineTrackData(enriched, selectedBest);
+      }
 
+      final enrichedIsrc = (enriched['isrc'] ?? '').trim();
       final needsIsrc =
-          _autoFillFields.contains('isrc') && enriched['isrc']!.isEmpty;
+          _autoFillFields.contains('isrc') && enrichedIsrc.isEmpty;
       final needsExtended =
           _autoFillFields.contains('genre') ||
           _autoFillFields.contains('label') ||
           _autoFillFields.contains('copyright') ||
           _autoFillFields.contains('composer');
 
-      final rawSpotifyId = _extractRawSpotifyTrackId(selectedBest);
+      final rawSpotifyId = selectedBest == null
+          ? _extractRawSpotifyTrackIdFromValue(widget.sourceTrackId)
+          : _extractRawSpotifyTrackId(selectedBest);
 
-      deezerId ??= _extractRawDeezerTrackId(selectedBest);
-      final candidateIsrc = enriched['isrc']!.trim().toUpperCase();
+      deezerId ??= selectedBest == null
+          ? null
+          : _extractRawDeezerTrackId(selectedBest);
+      final candidateIsrc = enrichedIsrc.toUpperCase();
       final deezerLookupIsrc = _looksLikeIsrc(currentIsrc)
           ? currentIsrc
           : (_looksLikeIsrc(candidateIsrc) ? candidateIsrc : '');
@@ -5243,7 +5287,9 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       if (!mounted) return;
 
       // Fetch ISRC from Deezer track metadata if still missing
-      if (needsIsrc && enriched['isrc']!.isEmpty && deezerId != null) {
+      if (needsIsrc &&
+          (enriched['isrc'] ?? '').trim().isEmpty &&
+          deezerId != null) {
         try {
           final deezerMeta = await PlatformBridge.getDeezerMetadata(
             'track',
@@ -5275,6 +5321,37 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
         }
       }
 
+      if (shouldFetchLyrics) {
+        final lyricsTitle =
+            ((selectedBest?['name'] ?? selectedBest?['title'] ?? title)
+                    .toString())
+                .trim();
+        final lyricsArtist =
+            ((selectedBest?['artists'] ?? selectedBest?['artist'] ?? artist)
+                    .toString())
+                .trim();
+
+        if (lyricsTitle.isNotEmpty && lyricsArtist.isNotEmpty) {
+          try {
+            final lyricsResult = await PlatformBridge.getLyricsLRCWithSource(
+              rawSpotifyId ?? '',
+              lyricsTitle,
+              lyricsArtist,
+              durationMs: widget.durationMs,
+            );
+            final lyricsText = lyricsResult['lyrics']?.toString().trim() ?? '';
+            final instrumental =
+                (lyricsResult['instrumental'] as bool? ?? false) ||
+                lyricsText == '[instrumental:true]';
+            if (!instrumental && lyricsText.isNotEmpty) {
+              enriched['lyrics'] = lyricsText;
+            }
+          } catch (e) {
+            _log.w('Lyrics autofill failed: $e');
+          }
+        }
+      }
+
       if (!mounted) return;
 
       var filledCount = 0;
@@ -5293,7 +5370,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
         }
       }
 
-      if (_autoFillFields.contains('cover')) {
+      if (_autoFillFields.contains('cover') && selectedBest != null) {
         final coverUrl =
             (selectedBest['cover_url'] ?? selectedBest['images'] ?? '')
                 .toString();
@@ -5369,6 +5446,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
     _discTotalCtrl = TextEditingController(text: v['total_discs'] ?? '');
     _genreCtrl = TextEditingController(text: v['genre'] ?? '');
     _isrcCtrl = TextEditingController(text: v['isrc'] ?? '');
+    _lyricsCtrl = TextEditingController(text: v['lyrics'] ?? '');
     _labelCtrl = TextEditingController(text: v['label'] ?? '');
     _copyrightCtrl = TextEditingController(text: v['copyright'] ?? '');
     _composerCtrl = TextEditingController(text: v['composer'] ?? '');
@@ -5391,6 +5469,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
     _discTotalCtrl.dispose();
     _genreCtrl.dispose();
     _isrcCtrl.dispose();
+    _lyricsCtrl.dispose();
     _labelCtrl.dispose();
     _copyrightCtrl.dispose();
     _composerCtrl.dispose();
@@ -5413,6 +5492,7 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
       'disc_total': _discTotalCtrl.text,
       'genre': _genreCtrl.text,
       'isrc': _isrcCtrl.text,
+      'lyrics': _lyricsCtrl.text,
       'label': _labelCtrl.text,
       'copyright': _copyrightCtrl.text,
       'composer': _composerCtrl.text,
@@ -5477,6 +5557,8 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
               : '',
           'GENRE': metadata['genre'] ?? '',
           'ISRC': metadata['isrc'] ?? '',
+          'LYRICS': metadata['lyrics'] ?? '',
+          'UNSYNCEDLYRICS': metadata['lyrics'] ?? '',
           'ORGANIZATION': metadata['label'] ?? '',
           'COPYRIGHT': metadata['copyright'] ?? '',
           'COMPOSER': metadata['composer'] ?? '',
@@ -5486,11 +5568,6 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
           final existingMetadata = await PlatformBridge.readFileMetadata(
             ffmpegTarget,
           );
-          final existingLyrics = existingMetadata['lyrics']?.toString().trim();
-          if (existingLyrics != null && existingLyrics.isNotEmpty) {
-            vorbisMap['LYRICS'] = existingLyrics;
-            vorbisMap['UNSYNCEDLYRICS'] = existingLyrics;
-          }
           // Preserve ReplayGain tags if present — these are computed once
           // during download and should survive manual metadata edits.
           final rgFields = <String, String>{
@@ -5717,6 +5794,12 @@ class _EditMetadataSheetState extends State<_EditMetadataSheet> {
                   ),
                   _field('Genre', _genreCtrl),
                   _field('ISRC', _isrcCtrl),
+                  _field(
+                    context.l10n.trackLyrics,
+                    _lyricsCtrl,
+                    maxLines: 8,
+                    keyboard: TextInputType.multiline,
+                  ),
                   Padding(
                     padding: const EdgeInsets.only(top: 8, bottom: 4),
                     child: InkWell(

lib/services/csv_import_service.dart

@@ -61,32 +61,29 @@ class CsvImportService {
         if (trackData == null) {
           try {
             final query = '${track.artistName} ${track.name}';
-            final searchResult = await PlatformBridge.searchDeezerAll(
+            final searchResult = await PlatformBridge.customSearchWithExtension(
+              'deezer',
               query,
-              trackLimit: 5,
+              options: {'filter': 'track', 'limit': 5},
             );
 
-            if (searchResult.containsKey('tracks')) {
-              final tracksList = searchResult['tracks'] as List<dynamic>?;
-              if (tracksList != null && tracksList.isNotEmpty) {
-                for (final result in tracksList) {
-                  final resultMap = result as Map<String, dynamic>;
-                  final resultName =
-                      (resultMap['name'] as String?)?.toLowerCase() ?? '';
-                  final trackNameLower = track.name.toLowerCase();
+            if (searchResult.isNotEmpty) {
+              for (final resultMap in searchResult) {
+                final resultName =
+                    (resultMap['name'] as String?)?.toLowerCase() ?? '';
+                final trackNameLower = track.name.toLowerCase();
 
-                  if (resultName.contains(trackNameLower) ||
-                      trackNameLower.contains(resultName)) {
-                    trackData = resultMap;
-                    _log.d('Text search match for ${track.name}: $resultName');
-                    break;
-                  }
+                if (resultName.contains(trackNameLower) ||
+                    trackNameLower.contains(resultName)) {
+                  trackData = resultMap;
+                  _log.d('Text search match for ${track.name}: $resultName');
+                  break;
                 }
+              }
 
-                if (trackData == null && tracksList.isNotEmpty) {
-                  trackData = tracksList.first as Map<String, dynamic>;
-                  _log.d('Using first search result for ${track.name}');
-                }
+              if (trackData == null) {
+                trackData = searchResult.first;
+                _log.d('Using first search result for ${track.name}');
               }
             }
           } catch (e) {

lib/services/ffmpeg_service.dart

@@ -1139,20 +1139,28 @@ class FFmpegService {
         : '.tmp';
     final tempDir = await getTemporaryDirectory();
     final tempOutput = _nextTempEmbedPath(tempDir.path, ext);
-
-    final sanitizedGain = albumGain.replaceAll('"', '\\"');
-    final sanitizedPeak = albumPeak.replaceAll('"', '\\"');
-
-    // -map_metadata 0 preserves all existing metadata from the input.
-    // -metadata flags add/overwrite only the specified keys.
-    final command =
-        '-v error -hide_banner -i "$filePath" -map 0 -c copy -map_metadata 0 '
-        '-metadata REPLAYGAIN_ALBUM_GAIN="$sanitizedGain" '
-        '-metadata REPLAYGAIN_ALBUM_PEAK="$sanitizedPeak" '
-        '"$tempOutput" -y';
+    final arguments = <String>[
+      '-v',
+      'error',
+      '-hide_banner',
+      '-i',
+      filePath,
+      '-map',
+      '0',
+      '-c',
+      'copy',
+      '-map_metadata',
+      '0',
+      '-metadata',
+      'REPLAYGAIN_ALBUM_GAIN=$albumGain',
+      '-metadata',
+      'REPLAYGAIN_ALBUM_PEAK=$albumPeak',
+      tempOutput,
+      '-y',
+    ];
 
     _log.d('Writing album ReplayGain tags via FFmpeg');
-    final result = await _execute(command);
+    final result = await _executeWithArguments(arguments);
 
     if (result.success) {
       try {
@@ -1194,41 +1202,50 @@ class FFmpegService {
   }) async {
     final tempDir = await getTemporaryDirectory();
     final tempOutput = _nextTempEmbedPath(tempDir.path, '.flac');
-
-    final StringBuffer cmdBuffer = StringBuffer();
-    cmdBuffer.write('-v error -hide_banner ');
-    cmdBuffer.write('-i "$flacPath" ');
+    final arguments = <String>['-v', 'error', '-hide_banner', '-i', flacPath];
 
     if (coverPath != null) {
-      cmdBuffer.write('-i "$coverPath" ');
+      arguments
+        ..add('-i')
+        ..add(coverPath);
     }
 
-    cmdBuffer.write('-map 0:a ');
+    arguments
+      ..add('-map')
+      ..add('0:a');
 
     if (coverPath != null) {
-      cmdBuffer.write('-map 1:0 ');
-      cmdBuffer.write('-c:v copy ');
-      cmdBuffer.write('-disposition:v attached_pic ');
-      cmdBuffer.write('-metadata:s:v title="Album cover" ');
-      cmdBuffer.write('-metadata:s:v comment="Cover (front)" ');
+      arguments
+        ..add('-map')
+        ..add('1:0')
+        ..add('-c:v')
+        ..add('copy')
+        ..add('-disposition:v')
+        ..add('attached_pic')
+        ..add('-metadata:s:v')
+        ..add('title=Album cover')
+        ..add('-metadata:s:v')
+        ..add('comment=Cover (front)');
     }
 
-    cmdBuffer.write('-c:a copy ');
+    arguments
+      ..add('-c:a')
+      ..add('copy');
 
     if (metadata != null) {
-      _appendVorbisMetadataToCommandBuffer(
-        cmdBuffer,
+      _appendVorbisMetadataToArguments(
+        arguments,
         metadata,
         artistTagMode: artistTagMode,
       );
     }
 
-    cmdBuffer.write('"$tempOutput" -y');
+    arguments
+      ..add(tempOutput)
+      ..add('-y');
 
-    final command = cmdBuffer.toString();
-    _log.d('Executing FFmpeg command: ${_previewCommandForLog(command)}');
-
-    final result = await _execute(command);
+    _log.d('Executing FFmpeg FLAC embed command');
+    final result = await _executeWithArguments(arguments);
 
     if (result.success) {
       try {
@@ -1274,46 +1291,50 @@ class FFmpegService {
   }) async {
     final tempDir = await getTemporaryDirectory();
     final tempOutput = _nextTempEmbedPath(tempDir.path, '.mp3');
-
-    final StringBuffer cmdBuffer = StringBuffer();
-    cmdBuffer.write('-v error -hide_banner ');
-    cmdBuffer.write('-i "$mp3Path" ');
+    final arguments = <String>['-v', 'error', '-hide_banner', '-i', mp3Path];
 
     if (coverPath != null) {
-      cmdBuffer.write('-i "$coverPath" ');
+      arguments
+        ..add('-i')
+        ..add(coverPath);
     }
 
-    cmdBuffer.write('-map 0:a ');
-    cmdBuffer.write(
-      preserveMetadata ? '-map_metadata 0 ' : '-map_metadata -1 ',
-    );
+    arguments
+      ..add('-map')
+      ..add('0:a')
+      ..add('-map_metadata')
+      ..add(preserveMetadata ? '0' : '-1');
 
     if (coverPath != null) {
-      cmdBuffer.write('-map 1:0 ');
-      cmdBuffer.write('-c:v:0 copy ');
-      cmdBuffer.write('-id3v2_version 3 ');
-      cmdBuffer.write('-metadata:s:v title="Album cover" ');
-      cmdBuffer.write('-metadata:s:v comment="Cover (front)" ');
+      arguments
+        ..add('-map')
+        ..add('1:0')
+        ..add('-c:v:0')
+        ..add('copy')
+        ..add('-id3v2_version')
+        ..add('3')
+        ..add('-metadata:s:v')
+        ..add('title=Album cover')
+        ..add('-metadata:s:v')
+        ..add('comment=Cover (front)');
     }
 
-    cmdBuffer.write('-c:a copy ');
+    arguments
+      ..add('-c:a')
+      ..add('copy');
 
     if (metadata != null) {
-      final id3Metadata = _convertToId3Tags(metadata);
-      id3Metadata.forEach((key, value) {
-        final sanitizedValue = value.replaceAll('"', '\\"');
-        cmdBuffer.write('-metadata $key="$sanitizedValue" ');
-      });
+      _appendMappedMetadataToArguments(arguments, _convertToId3Tags(metadata));
     }
 
-    cmdBuffer.write('-id3v2_version 3 "$tempOutput" -y');
+    arguments
+      ..add('-id3v2_version')
+      ..add('3')
+      ..add(tempOutput)
+      ..add('-y');
 
-    final command = cmdBuffer.toString();
-    _log.d(
-      'Executing FFmpeg MP3 embed command: ${_previewCommandForLog(command)}',
-    );
-
-    final result = await _execute(command);
+    _log.d('Executing FFmpeg MP3 embed command');
+    final result = await _executeWithArguments(arguments);
 
     if (result.success) {
       try {
@@ -1452,14 +1473,11 @@ class FFmpegService {
     required String m4aPath,
     String? coverPath,
     Map<String, String>? metadata,
-    bool preserveMetadata = false,
+    bool preserveMetadata = true,
   }) async {
     final tempDir = await getTemporaryDirectory();
     final tempOutput = _nextTempEmbedPath(tempDir.path, '.m4a');
-
-    final cmdBuffer = StringBuffer();
-    cmdBuffer.write('-v error -hide_banner ');
-    cmdBuffer.write('-i "$m4aPath" ');
+    final arguments = <String>['-v', 'error', '-hide_banner', '-i', m4aPath];
 
     final normalizedCoverPath = coverPath?.trim();
     final hasCover =
@@ -1467,48 +1485,61 @@ class FFmpegService {
         normalizedCoverPath.isNotEmpty &&
         await File(normalizedCoverPath).exists();
     if (hasCover) {
-      cmdBuffer.write('-i "$normalizedCoverPath" ');
+      arguments
+        ..add('-i')
+        ..add(normalizedCoverPath);
     }
 
     final preserveExistingStreams = preserveMetadata && !hasCover;
     if (preserveExistingStreams) {
       // When no replacement cover is provided, preserve all input streams so
       // the existing attached artwork is not dropped during the metadata rewrite.
-      cmdBuffer.write('-map 0 -c copy ');
+      arguments
+        ..add('-map')
+        ..add('0')
+        ..add('-c')
+        ..add('copy');
     } else {
-      cmdBuffer.write('-map 0:a -c:a copy ');
+      arguments
+        ..add('-map')
+        ..add('0:a')
+        ..add('-c:a')
+        ..add('copy');
     }
-    cmdBuffer.write(
-      preserveMetadata ? '-map_metadata 0 ' : '-map_metadata -1 ',
-    );
+    arguments
+      ..add('-map_metadata')
+      ..add(preserveMetadata ? '0' : '-1');
 
     // For M4A cover replacements, mark the image as an attached picture so the
     // mp4 muxer writes a proper covr atom instead of a generic MJPEG video track.
     // Force the mp4 muxer because the default ipod muxer (auto-selected for .m4a)
     // does not register a codec tag for mjpeg on FFmpeg 8.0+.
     if (hasCover) {
-      cmdBuffer.write('-map 1:v -c:v copy -disposition:v:0 attached_pic ');
-      cmdBuffer.write('-metadata:s:v title="Album cover" ');
-      cmdBuffer.write('-metadata:s:v comment="Cover (front)" ');
-      cmdBuffer.write('-f mp4 ');
+      arguments
+        ..add('-map')
+        ..add('1:v')
+        ..add('-c:v')
+        ..add('copy')
+        ..add('-disposition:v:0')
+        ..add('attached_pic')
+        ..add('-metadata:s:v')
+        ..add('title=Album cover')
+        ..add('-metadata:s:v')
+        ..add('comment=Cover (front)')
+        ..add('-f')
+        ..add('mp4');
     }
 
     if (metadata != null) {
-      final m4aMetadata = _convertToM4aTags(metadata);
-      for (final entry in m4aMetadata.entries) {
-        final sanitizedValue = entry.value.replaceAll('"', '\\"');
-        cmdBuffer.write('-metadata ${entry.key}="$sanitizedValue" ');
-      }
+      _appendMappedMetadataToArguments(arguments, _convertToM4aTags(metadata));
     }
 
-    cmdBuffer.write('"$tempOutput" -y');
+    arguments
+      ..add(tempOutput)
+      ..add('-y');
 
-    final command = cmdBuffer.toString();
-    _log.d(
-      'Executing FFmpeg M4A embed command: ${_previewCommandForLog(command)}',
-    );
-
-    final result = await _execute(command);
+    _log.d('Executing FFmpeg M4A embed command');
+    final result = await _executeWithArguments(arguments);
 
     if (result.success) {
       try {
@@ -1767,40 +1798,50 @@ class FFmpegService {
     bool deleteOriginal = true,
   }) async {
     final outputPath = _buildOutputPath(inputPath, '.m4a');
-
-    final cmdBuffer = StringBuffer();
-    cmdBuffer.write('-v error -hide_banner ');
-    cmdBuffer.write('-i "$inputPath" ');
+    final arguments = <String>['-v', 'error', '-hide_banner', '-i', inputPath];
 
     final hasCover =
         coverPath != null &&
         coverPath.trim().isNotEmpty &&
         await File(coverPath).exists();
     if (hasCover) {
-      cmdBuffer.write('-i "$coverPath" ');
+      arguments
+        ..add('-i')
+        ..add(coverPath);
     }
 
-    cmdBuffer.write('-map 0:a ');
+    arguments
+      ..add('-map')
+      ..add('0:a');
     if (hasCover) {
-      cmdBuffer.write('-map 1:v -c:v copy -disposition:v:0 attached_pic ');
-      cmdBuffer.write('-metadata:s:v title="Album cover" ');
-      cmdBuffer.write('-metadata:s:v comment="Cover (front)" ');
+      arguments
+        ..add('-map')
+        ..add('1:v')
+        ..add('-c:v')
+        ..add('copy')
+        ..add('-disposition:v:0')
+        ..add('attached_pic')
+        ..add('-metadata:s:v')
+        ..add('title=Album cover')
+        ..add('-metadata:s:v')
+        ..add('comment=Cover (front)');
     }
-    cmdBuffer.write('-c:a alac ');
-    cmdBuffer.write('-map_metadata -1 ');
+    arguments
+      ..add('-c:a')
+      ..add('alac')
+      ..add('-map_metadata')
+      ..add('-1');
 
-    final m4aTags = _convertToM4aTags(metadata);
-    for (final entry in m4aTags.entries) {
-      final sanitized = entry.value.replaceAll('"', '\\"');
-      cmdBuffer.write('-metadata ${entry.key}="$sanitized" ');
-    }
+    _appendMappedMetadataToArguments(arguments, _convertToM4aTags(metadata));
 
-    cmdBuffer.write('"$outputPath" -y');
+    arguments
+      ..add(outputPath)
+      ..add('-y');
 
     _log.i(
       'Converting ${inputPath.split(Platform.pathSeparator).last} to ALAC',
     );
-    final result = await _execute(cmdBuffer.toString());
+    final result = await _executeWithArguments(arguments);
 
     if (!result.success) {
       _log.e('ALAC conversion failed: ${result.output}');
@@ -1830,40 +1871,56 @@ class FFmpegService {
     bool deleteOriginal = true,
   }) async {
     final outputPath = _buildOutputPath(inputPath, '.flac');
-
-    final cmdBuffer = StringBuffer();
-    cmdBuffer.write('-v error -hide_banner ');
-    cmdBuffer.write('-i "$inputPath" ');
+    final arguments = <String>['-v', 'error', '-hide_banner', '-i', inputPath];
 
     final hasCover =
         coverPath != null &&
         coverPath.trim().isNotEmpty &&
         await File(coverPath).exists();
     if (hasCover) {
-      cmdBuffer.write('-i "$coverPath" ');
+      arguments
+        ..add('-i')
+        ..add(coverPath);
     }
 
-    cmdBuffer.write('-map 0:a ');
+    arguments
+      ..add('-map')
+      ..add('0:a');
     if (hasCover) {
-      cmdBuffer.write('-map 1:v -c:v copy -disposition:v:0 attached_pic ');
-      cmdBuffer.write('-metadata:s:v title="Album cover" ');
-      cmdBuffer.write('-metadata:s:v comment="Cover (front)" ');
+      arguments
+        ..add('-map')
+        ..add('1:v')
+        ..add('-c:v')
+        ..add('copy')
+        ..add('-disposition:v:0')
+        ..add('attached_pic')
+        ..add('-metadata:s:v')
+        ..add('title=Album cover')
+        ..add('-metadata:s:v')
+        ..add('comment=Cover (front)');
     }
-    cmdBuffer.write('-c:a flac -compression_level 8 ');
-    cmdBuffer.write('-map_metadata 0 ');
+    arguments
+      ..add('-c:a')
+      ..add('flac')
+      ..add('-compression_level')
+      ..add('8')
+      ..add('-map_metadata')
+      ..add('0');
 
-    _appendVorbisMetadataToCommandBuffer(
-      cmdBuffer,
+    _appendVorbisMetadataToArguments(
+      arguments,
       metadata,
       artistTagMode: artistTagMode,
     );
 
-    cmdBuffer.write('"$outputPath" -y');
+    arguments
+      ..add(outputPath)
+      ..add('-y');
 
     _log.i(
       'Converting ${inputPath.split(Platform.pathSeparator).last} to FLAC',
     );
-    final result = await _execute(cmdBuffer.toString());
+    final result = await _executeWithArguments(arguments);
 
     if (!result.success) {
       _log.e('FLAC conversion failed: ${result.output}');
@@ -1921,8 +1978,14 @@ class FFmpegService {
           break;
         case 'DATE':
           vorbis['DATE'] = value;
+          final yearMatch = RegExp(r'^(\d{4})').firstMatch(value);
+          if (yearMatch != null &&
+              (!vorbis.containsKey('YEAR') || vorbis['YEAR']!.isEmpty)) {
+            vorbis['YEAR'] = yearMatch.group(1)!;
+          }
           break;
         case 'YEAR':
+          vorbis['YEAR'] = value;
           if (!vorbis.containsKey('DATE') || vorbis['DATE']!.isEmpty) {
             vorbis['DATE'] = value;
           }
@@ -1969,20 +2032,6 @@ class FFmpegService {
     return vorbis;
   }
 
-  static void _appendVorbisMetadataToCommandBuffer(
-    StringBuffer cmdBuffer,
-    Map<String, String> metadata, {
-    String artistTagMode = artistTagModeJoined,
-  }) {
-    for (final entry in _buildVorbisMetadataEntries(
-      metadata,
-      artistTagMode: artistTagMode,
-    )) {
-      final sanitized = entry.value.replaceAll('"', '\\"');
-      cmdBuffer.write('-metadata ${entry.key}="$sanitized" ');
-    }
-  }
-
   static void _appendVorbisMetadataToArguments(
     List<String> arguments,
     Map<String, String> metadata, {
@@ -1998,6 +2047,17 @@ class FFmpegService {
     }
   }
 
+  static void _appendMappedMetadataToArguments(
+    List<String> arguments,
+    Map<String, String> metadata,
+  ) {
+    for (final entry in metadata.entries) {
+      arguments
+        ..add('-metadata')
+        ..add('${entry.key}=${entry.value}');
+    }
+  }
+
   static List<MapEntry<String, String>> _buildVorbisMetadataEntries(
     Map<String, String> metadata, {
     String artistTagMode = artistTagModeJoined,
@@ -2115,19 +2175,6 @@ class FFmpegService {
         case 'UNSYNCEDLYRICS':
           m4aMap['lyrics'] = value;
           break;
-        // ReplayGain as iTunes freeform atoms (com.apple.iTunes:replaygain_*)
-        case 'REPLAYGAINTRACKGAIN':
-          m4aMap['REPLAYGAIN_TRACK_GAIN'] = value;
-          break;
-        case 'REPLAYGAINTRACKPEAK':
-          m4aMap['REPLAYGAIN_TRACK_PEAK'] = value;
-          break;
-        case 'REPLAYGAINALBUMGAIN':
-          m4aMap['REPLAYGAIN_ALBUM_GAIN'] = value;
-          break;
-        case 'REPLAYGAINALBUMPEAK':
-          m4aMap['REPLAYGAIN_ALBUM_PEAK'] = value;
-          break;
       }
     }
 
@@ -2255,23 +2302,36 @@ class FFmpegService {
       final trackNumStr = track.number.toString().padLeft(2, '0');
       final outputFileName = '$trackNumStr - $sanitizedTitle.$outputExt';
       final outputPath = '$outputDir${Platform.pathSeparator}$outputFileName';
-
-      final StringBuffer cmdBuffer = StringBuffer();
-      cmdBuffer.write('-v error -hide_banner ');
-      cmdBuffer.write('-i "$audioPath" ');
+      final arguments = <String>[
+        '-v',
+        'error',
+        '-hide_banner',
+        '-i',
+        audioPath,
+      ];
 
       final startTime = _formatSecondsForFFmpeg(track.startSec);
-      cmdBuffer.write('-ss $startTime ');
+      arguments
+        ..add('-ss')
+        ..add(startTime);
 
       if (track.endSec > 0) {
         final endTime = _formatSecondsForFFmpeg(track.endSec);
-        cmdBuffer.write('-to $endTime ');
+        arguments
+          ..add('-to')
+          ..add(endTime);
       }
 
       if (outputExt == 'flac') {
-        cmdBuffer.write('-c:a flac -compression_level 8 ');
+        arguments
+          ..add('-c:a')
+          ..add('flac')
+          ..add('-compression_level')
+          ..add('8');
       } else {
-        cmdBuffer.write('-c:a copy ');
+        arguments
+          ..add('-c:a')
+          ..add('copy');
       }
 
       final artist = track.artist.isNotEmpty
@@ -2280,11 +2340,11 @@ class FFmpegService {
       final album = albumMetadata['album'] ?? '';
       final genre = albumMetadata['genre'] ?? '';
       final date = albumMetadata['date'] ?? '';
+      final cueMetadata = <String, String>{};
 
       void addMeta(String key, String value) {
         if (value.isNotEmpty) {
-          final sanitized = value.replaceAll('"', '\\"');
-          cmdBuffer.write('-metadata $key="$sanitized" ');
+          cueMetadata[key] = value;
         }
       }
 
@@ -2298,14 +2358,13 @@ class FFmpegService {
       if (track.isrc.isNotEmpty) addMeta('ISRC', track.isrc);
       if (track.composer.isNotEmpty) addMeta('COMPOSER', track.composer);
 
-      cmdBuffer.write('"$outputPath" -y');
+      _appendMappedMetadataToArguments(arguments, cueMetadata);
+      arguments
+        ..add(outputPath)
+        ..add('-y');
 
-      final command = cmdBuffer.toString();
-      _log.d(
-        'CUE split track ${track.number}: ${_previewCommandForLog(command)}',
-      );
-
-      final result = await _execute(command);
+      _log.d('CUE split track ${track.number}');
+      final result = await _executeWithArguments(arguments);
       if (!result.success) {
         _log.e('CUE split failed for track ${track.number}: ${result.output}');
         continue;

lib/services/platform_bridge.dart

@@ -496,21 +496,6 @@ class PlatformBridge {
     await _channel.invokeMethod('clearTrackCache');
   }
 
-  static Future<Map<String, dynamic>> searchDeezerAll(
-    String query, {
-    int trackLimit = 15,
-    int artistLimit = 2,
-    String? filter,
-  }) async {
-    final result = await _channel.invokeMethod('searchDeezerAll', {
-      'query': query,
-      'track_limit': trackLimit,
-      'artist_limit': artistLimit,
-      'filter': filter ?? '',
-    });
-    return jsonDecode(result as String) as Map<String, dynamic>;
-  }
-
   static Future<Map<String, dynamic>> searchTidalAll(
     String query, {
     int trackLimit = 15,

lib/services/share_intent_service.dart

@@ -13,27 +13,9 @@ class ShareIntentService {
   static final RegExp _spotifyUriPattern = RegExp(
     r'spotify:(track|album|playlist|artist):[a-zA-Z0-9]+',
   );
-  static final RegExp _spotifyUrlPattern = RegExp(
-    r'https?://open\.spotify\.com/(track|album|playlist|artist)/[a-zA-Z0-9]+(\?[^\s]*)?',
-  );
-
-  static final RegExp _deezerUrlPattern = RegExp(
-    r'https?://(www\.)?deezer\.com/(track|album|playlist|artist)/\d+(\?[^\s]*)?',
-  );
-  static final RegExp _deezerShortLinkPattern = RegExp(
-    r'https?://deezer\.page\.link/[a-zA-Z0-9]+',
-  );
-
-  static final RegExp _tidalUrlPattern = RegExp(
-    r'https?://(listen\.)?tidal\.com/(track|album|playlist|artist)/[a-zA-Z0-9-]+(\?[^\s]*)?',
-  );
-
-  static final RegExp _ytMusicUrlPattern = RegExp(
-    r'https?://music\.youtube\.com/(watch\?v=|playlist\?list=|channel/|browse/)[a-zA-Z0-9_-]+([?&][^\s]*)?',
-  );
-
-  static final RegExp _youtubeUrlPattern = RegExp(
-    r'https?://(youtu\.be/[a-zA-Z0-9_-]+|www\.youtube\.com/watch\?v=[a-zA-Z0-9_-]+)([?&][^\s]*)?',
+  static final RegExp _genericHttpUrlPattern = RegExp(
+    "https?://[^\\s<>\\\"']+",
+    caseSensitive: false,
   );
 
   final _sharedUrlController = StreamController<String>.broadcast();
@@ -99,24 +81,17 @@ class ShareIntentService {
       return uriMatch.group(0);
     }
 
-    final patterns = [
-      _spotifyUrlPattern,
-      _deezerUrlPattern,
-      _deezerShortLinkPattern,
-      _tidalUrlPattern,
-      _ytMusicUrlPattern,
-      _youtubeUrlPattern,
-    ];
+    // Keep share parsing generic and let manifest-based URL handlers decide
+    // which installed extension can handle the incoming link.
+    for (final match in _genericHttpUrlPattern.allMatches(text)) {
+      final rawUrl = match.group(0);
+      if (rawUrl == null || rawUrl.isEmpty) {
+        continue;
+      }
 
-    for (final pattern in patterns) {
-      final match = pattern.firstMatch(text);
-      if (match != null) {
-        final fullUrl = match.group(0)!;
-        if (pattern == _ytMusicUrlPattern || pattern == _youtubeUrlPattern) {
-          return fullUrl;
-        }
-        final queryIndex = fullUrl.indexOf('?');
-        return queryIndex > 0 ? fullUrl.substring(0, queryIndex) : fullUrl;
+      final sanitizedUrl = rawUrl.replaceFirst(RegExp(r'[.,;:!?)\]}]+$'), '');
+      if (sanitizedUrl.isNotEmpty) {
+        return sanitizedUrl;
       }
     }
 

lib/utils/clickable_metadata.dart

@@ -10,6 +10,19 @@ import 'package:spotiflac_android/utils/artist_utils.dart';
 import 'package:spotiflac_android/utils/logger.dart';
 
 final _log = AppLogger('ClickableMetadata');
+const _deezerExtensionId = 'deezer';
+
+Future<List<Map<String, dynamic>>> _searchDeezerExtension(
+  String query, {
+  required String filter,
+  int limit = 5,
+}) {
+  return PlatformBridge.customSearchWithExtension(
+    _deezerExtensionId,
+    query,
+    options: {'filter': filter, 'limit': limit},
+  );
+}
 
 Future<void> navigateToArtist(
   BuildContext context, {
@@ -39,15 +52,14 @@ Future<void> navigateToArtist(
 
   _showLoadingSnackBar(context, 'Looking up artist...');
   try {
-    final results = await PlatformBridge.searchDeezerAll(
+    final artistList = await _searchDeezerExtension(
       artistName,
-      trackLimit: 0,
-      artistLimit: 3,
+      filter: 'artist',
+      limit: 3,
     );
     if (!context.mounted) return;
     ScaffoldMessenger.of(context).hideCurrentSnackBar();
 
-    final artistList = results['artists'] as List<dynamic>? ?? [];
     if (artistList.isEmpty) {
       _showUnavailable(context, 'Artist');
       return;
@@ -56,15 +68,13 @@ Future<void> navigateToArtist(
     Map<String, dynamic>? bestMatch;
     final lowerName = artistName.toLowerCase().trim();
     for (final a in artistList) {
-      if (a is Map<String, dynamic>) {
-        final name = (a['name'] as String? ?? '').toLowerCase().trim();
-        if (name == lowerName) {
-          bestMatch = a;
-          break;
-        }
+      final name = (a['name'] as String? ?? '').toLowerCase().trim();
+      if (name == lowerName) {
+        bestMatch = a;
+        break;
       }
     }
-    bestMatch ??= artistList.first as Map<String, dynamic>;
+    bestMatch ??= artistList.first;
 
     final resolvedId = bestMatch['id'] as String? ?? '';
     final resolvedName = bestMatch['name'] as String? ?? artistName;
@@ -81,6 +91,7 @@ Future<void> navigateToArtist(
       artistId: resolvedId,
       artistName: resolvedName,
       coverUrl: resolvedImage ?? coverUrl,
+      extensionId: _deezerExtensionId,
     );
   } catch (e) {
     _log.e('Failed to look up artist "$artistName": $e', e);
@@ -125,15 +136,14 @@ Future<void> navigateToAlbum(
         ? '$albumName $artistName'
         : albumName;
 
-    final results = await PlatformBridge.searchDeezerAll(
+    final albumList = await _searchDeezerExtension(
       query,
-      trackLimit: 0,
-      artistLimit: 0,
+      filter: 'album',
+      limit: 5,
     );
     if (!context.mounted) return;
     ScaffoldMessenger.of(context).hideCurrentSnackBar();
 
-    final albumList = results['albums'] as List<dynamic>? ?? [];
     if (albumList.isEmpty) {
       _showUnavailable(context, 'Album');
       return;
@@ -142,15 +152,13 @@ Future<void> navigateToAlbum(
     Map<String, dynamic>? bestMatch;
     final lowerName = albumName.toLowerCase().trim();
     for (final a in albumList) {
-      if (a is Map<String, dynamic>) {
-        final name = (a['name'] as String? ?? '').toLowerCase().trim();
-        if (name == lowerName) {
-          bestMatch = a;
-          break;
-        }
+      final name = (a['name'] as String? ?? '').toLowerCase().trim();
+      if (name == lowerName) {
+        bestMatch = a;
+        break;
       }
     }
-    bestMatch ??= albumList.first as Map<String, dynamic>;
+    bestMatch ??= albumList.first;
 
     final resolvedId = bestMatch['id'] as String? ?? '';
     final resolvedName = bestMatch['name'] as String? ?? albumName;
@@ -167,6 +175,7 @@ Future<void> navigateToAlbum(
       albumId: resolvedId,
       albumName: resolvedName,
       coverUrl: resolvedImage ?? coverUrl,
+      extensionId: _deezerExtensionId,
     );
   } catch (e) {
     _log.e('Failed to look up album "$albumName": $e', e);
@@ -207,7 +216,7 @@ void _pushAlbumScreen(
   String? coverUrl,
   String? extensionId,
 }) {
-  const builtInProviders = {'tidal', 'qobuz', 'deezer'};
+  const builtInProviders = {'tidal', 'qobuz'};
   final isExtension =
       extensionId != null && !builtInProviders.contains(extensionId);
   final resolvedExtensionId = extensionId;