Greasy Fork is available in English.
Adds a progress bars (or dots) at bottom of video, a progress text which includes video quality and subtitle indicators, and a chapter title box on the YouTube video page.
< Opinie na Add YouTube Video Progress
Script has been updated. Sorry for the (very) late fix.
I'm unable to saved my settings in your script. I use Firefox or Edge, with either TamperMonkey or VioletMonkey, with a clean profile. Otherwise an excellent script.