Audio/video player is blank in 6.5a2

A blog commenter writes: Previous builds would have a dark background with simple controls for video or audio playback. There are no longer visible controls for video/audio, just a blank white background, and I cannot view statistics or seek. Same behavior from local files [mp3/4].

I can reproduce this. The player plays but there are no controls; in the case of an audio file this means the whole page is blank. It works as expected in 6.0.3.

Try these example URLs: https://archive.org/download/OrsonWellesMrBruns/381030.ogg (audio) https://extra.torproject.org/blog/2016-08-PT-animation/pluggable_transports-animation.mp4 (video)

Here is how the audio player looks in 6.0.3: And in 6.5a2 it's just blank: