Marcin Borkowski often watches long YouTube videos (frequently lectures) and sometimes can’t watch the whole thing in a single sitting. A couple of weeks ago, he wrote a post about capturing the elapsed play time where he left off and adding it to a link to the video that he maintained within Org-mode. That way when he followed the link, the video would start where he left off.
He’s discovered what he describes as a “much much better solution” to the problem. And it really is. He leverages a youtube-dl fork and mpv to play YouTube videos directly from Emacs. That’s already pretty nice but mpv can also remember where you left off so that you don’t need anything fancy to help you remember. There are a couple of ways of doing that so be sure to check out Borkowski’s post for the details.
Oddly, the code to do all this is simpler and shorter than the code to capture the time and add it to a link. If you want to store links to YouTube videos for later watching and be able to remember how much you’ve watched, this is a great solution.