diff --git a/lib/coreBundle.js b/lib/coreBundle.js
index 6893f1cf133efec2c5dccc35c77cc7a53870ccbc..7990e202c5b574ca5ea4c3e73c15c2da43a5b980 100644
--- a/lib/coreBundle.js
+++ b/lib/coreBundle.js
@@ -10031,6 +10031,10 @@ 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);
@@ -36204,7 +36208,10 @@ 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",