219399 2020-12-01 08:23:04 -0800 [Media] Play promise rejection in HTMLMediaElement 2021-02-09 22:09:03 -0800 1 1 1 Unclassified WebKit Media WebKit Nightly Build Unspecified Unspecified NEW https://bugs.webkit.org/show_bug.cgi?id=200344 InRadar P2 Normal --- 1 wojtas.arkadiusz webkit-unassigned eric.carlson fjimenez jer.noble peng.liu6 smoley webkit-bug-importer oldest_to_newest 1711042 0 wojtas.arkadiusz 2020-12-01 08:23:04 -0800 The HTMLMediaElement rejects play promise when the webpage's playback call sequence is: 1) create a video element 2) call video.play() 3) sets the src attribute That sequence in WPEWebkit is not handled correctly. Setting the src attribute results in play promise rejection. I have compared that with chromium and it handles that situation in a different way. The algorithm is described here: https://html.spec.whatwg.org/multipage/media.html#media-element-load-algorithm In the chromium the HTMLMediaElement cancels events, resolve promises that are scheduled to be resolved and rejects play promises that are scheduled to be rejected (Step 3 and 4). The rest of the play promises are not touched (unless step 6 takes place). In webkit's step 3: all events and promises are rejected. It is done by cancelPendingEventsAndCallbacks. 1712508 1 webkit-bug-importer 2020-12-07 11:19:27 -0800 <rdar://problem/72055839>