About the wizard, it would help if you just had a "Subtitles" checkbox somewhere which then adds a blank <track> line to the script. As for the synthax questio

About the wizard, it would help if you just had a "Subtitles" checkbox somewhere which then adds a blank <track> line to the script. As for the synthax question, my point is that your script looks like this <video slot="media" src="https://stream.mux.com/fXNzVtmtWuyz00xnSrJg4OJH6PyNo6D02UzmgeKGkP5YQ/low.mp4" playsinline crossorigin ></video> And media chorme looks like this <video slot="media" src="./video.mp4" crossOrigin playsInline> <track label="English" kind="captions" srcLang="en" src="./captions.vtt"></track> <track label="thumbnails" default kind="metadata" src="./thumbnails.vtt"></track> </video> And I just don't know how to interpolate the two (Edit, checking further, I did manage to mix the two, and I can play subtitles over your demo video, but not over mine so I guess a foolproof sample in the wizard is probably needed :D )