YouTube/Twitch Bookmarker от Stoyko Bogev

This extension is suitable for people who don't watch a video from start to end.

It creates a bookmark in the Bookmarks Toolbar for quick access with the video timestamp so you can start from where you stopped watching.

Previously bookmarked video is updated instead of creating a new one, given the title has not been changed or the bookmark moved into a folder. This removes the need to delete the old bookmark when watching long videos and there are several interruptions.