Subtitle and caption support for many sites in Firefox's Picture-in-Picture player window is targeted to ship in Firefox 100.
Hi! If you're reading this, then you've asked me about or otherwise expressed interest in supporting captions / subtitles in Firefox's Picture-in-Picture feature.
As of this writing, Firefox does not currently support captions or subtitles in the player window. This is because most sites have invented their own mechanisms for display captions or subtitles. YouTube's captions, for example, are implemented in a completely different way from Netflix's.
This makes it rather difficult for us as a browser to develop a general solution to the subtitles / caption problem.
~Difficult, but not impossible. We're currently working on ways for us to develop site-specific behaviours for Picture-in-Picture. This allows Firefox's Picture-in-Picture feature to be smarter in how it interacts with specific video sites. In theory, this would allow us to detect the subtitles and captions and disp