Created attachment 423964 [details] Minimal bug example with instructions When a WebGL texture is being updated with frames from a looping playing video element through calls to `gl.texImage2d()`, a set of conditions will intermittently cause it to freeze when it reaches its end. The set of conditions is: - The video has no audio track. - The video is looping. - `gl.texImage2d()` gets called when the video's `currentTime` is 0. This happens far more often when the system is under heavy load (many other Safari tabs and windows are open doing lots of work). At the point the video freezes: - The WebGL texture stops visibly updating. - The video's `currentTime` stops changing. - `timeupdate` events stop firing. - `video.seeking` is false. - `video.paused` is false. I have reproduced the issue with a minimal html/js file and public domain video, which I've attached in a zip archive. Open it in Safari with the system under load and refresh repeatedly until the video freezes on its last frame. The example code has two booleans near the top. The bug will not manifest if either is set to false.
<rdar://problem/75980644>