diff --git a/lib/coreBundle.js b/lib/coreBundle.js
index d9041dd0f009072511a7d808dec83121ff29e127..542acd31dd7e8ae084de952dc42ec63d0caba849 100644
--- a/lib/coreBundle.js
+++ b/lib/coreBundle.js
@@ -8906,6 +8906,10 @@ async function launchProcess(options) {
     env: options.env,
     cwd: options.cwd,
     shell: options.shell,
+    // gstack patch (#2160/#1989): Node defaults windowsHide to false for
+    // child_process.spawn, so browser children could flash a console window
+    // on Windows. Playwright never needs the child's window shown.
+    windowsHide: true,
     stdio
   };
   const spawnedProcess = childProcess.spawn(options.command, options.args || [], spawnOptions);
@@ -8985,7 +8989,7 @@ async function launchProcess(options) {
       options.log(`[pid=${spawnedProcess.pid}] <will force kill>`);
       try {
         if (process.platform === "win32") {
-          const taskkillProcess = childProcess.spawnSync(`taskkill /pid ${spawnedProcess.pid} /T /F`, { shell: true });
+          const taskkillProcess = childProcess.spawnSync(`taskkill /pid ${spawnedProcess.pid} /T /F`, { shell: true, windowsHide: true });
           const [stdout2, stderr2] = [taskkillProcess.stdout.toString(), taskkillProcess.stderr.toString()];
           if (stdout2)
             options.log(`[pid=${spawnedProcess.pid}] taskkill stdout: ${stdout2}`);
@@ -34634,7 +34638,10 @@ var init_chromiumSwitches = __esm({
       // Disables forced sign-in in Edge.
       "msForceBrowserSignIn",
       // Disables updating the preferred version in LaunchServices preferences on mac.
-      "msEdgeUpdateLaunchServicesPreferredVersion"
+      "msEdgeUpdateLaunchServicesPreferredVersion",
+      // gstack patch: backport of microsoft/playwright#43605 (1.65). Random client ports fail with
+      // net::ERR_NO_BUFFER_SPACE (WSAENOBUFS) on Windows even when ports are free (crbug.com/572515601).
+      "TcpPortRandomizationWin"
     ].filter(Boolean);
     chromiumSwitches = (options) => [
       "--disable-field-trial-config",