fix: handle page restoration from bfcache in Safari (#7683)

christriants · web-flow · commit 51725fcc81de · 2026-01-15T17:31:27.000-08:00
diff --git a/src/controller/buffer-controller.ts b/src/controller/buffer-controller.ts
@@ -1575,6 +1575,15 @@ transfer tracks: ${stringify(transferredTracks, (key, value) => (key === 'initSe
 
   private _onMediaSourceClose = () => {
     this.log('Media source closed');
+    // Safari/WebKit bug: MediaSource becomes invalid after bfcache restoration.
+    // When the user navigates back, the MediaSource is in a 'closed' state and cannot be used.
+    // If sourceclose fires while media is still attached, trigger recovery to reattach media.
+    if (this.media) {
+      this.warn(
+        'MediaSource closed while media attached - triggering recovery',
+      );
+      this.hls.recoverMediaError();
+    }
   };
 
   private _onMediaSourceEnded = () => {
diff --git a/tests/unit/controller/buffer-controller.ts b/tests/unit/controller/buffer-controller.ts
@@ -57,6 +57,7 @@ type BufferControllerTestable = Omit<
   sourceBuffers: SourceBuffersTuple;
   tracks: SourceBufferTrackSet;
   tracksReady: boolean;
+  _onMediaSourceClose: () => void;
 };
 
 describe('BufferController', function () {
@@ -557,4 +558,25 @@ describe('BufferController', function () {
       expect(bufferController.bufferedToEnd).to.be.true;
     });
   });
+
+  describe('Safari MediaSource bfcache close recovery', function () {
+    it('triggers recoverMediaError when sourceclose fires with media attached', function () {
+      const media = new MockMediaElement() as unknown as HTMLMediaElement;
+      const mediaSource = new MockMediaSource() as unknown as MediaSource;
+      const recoverMediaErrorSpy = sandbox.spy(hls, 'recoverMediaError');
+      bufferController.media = media;
+      bufferController.mediaSource = mediaSource;
+      bufferController._onMediaSourceClose();
+      expect(recoverMediaErrorSpy).to.have.been.calledOnce;
+    });
+
+    it('does not trigger recovery when sourceclose fires without media attached', function () {
+      const mediaSource = new MockMediaSource() as unknown as MediaSource;
+      const recoverMediaErrorSpy = sandbox.spy(hls, 'recoverMediaError');
+      bufferController.media = null;
+      bufferController.mediaSource = mediaSource;
+      bufferController._onMediaSourceClose();
+      expect(recoverMediaErrorSpy).to.not.have.been.called;
+    });
+  });
 });
