When I open https://twitter.com/bindermichi/status/1142102180142432258 firefox kind of crashes (flickers) and all images disappear and the current site becomes "white" and I have to reload. It is a bit hard to explain. In the console I see the following error: Media resource https://video.twimg.com/tweet_video/D9mP3uSXUAEll9A.mp4 could not be decoded. 1142102180142432258 Media resource https://video.twimg.com/tweet_video/D9mP3uSXUAEll9A.mp4 could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_FATAL_ERR (0x806e0005) 1142102180142432258