Adding Video Captions/Subtitles to Uploaded (Not Embedded) Videos

Hi there,

I'm experimenting with uploading .mp4 videos directly to Squarespace rather than embedding YouTube/Vimeo videos. It works fine but there doesn't seem to be any way to add a caption file, and the video player doesn't include closed caption options when you click on the little gear icon. When I look at the code, it seems that Squarespace includes a <div class="plyr__captions"></div> for captions, but it's empty.

I thought I'd try uploading a caption file to Squarespace's CDN and then use a code block with <video> and <track> tags to create a player (thusly: https://developer.mozilla.org/en-US/docs/Web/Guide/Audio_and_video_delivery/Adding_captions_and_subtitles_to_HTML5_video) but before I go about reinventing the wheel ... does anyone have experience with adding subtitles/captions to an uploaded (not embedded) video in Squarespace?

Thanks in advance,

Prescott