Greasy Fork is available in English.
Automatically continue watching YouTube videos on your favourite channels where you left off.
< Rückmeldungen auf YouTube Auto Resume
Use this guy's script: YouTube Resume It doesn't have the features I've added, which you listed above, and is basically what you want.
2 questions: Autoresume by default & hide option button
Which line(s) in your script do I have to change in order to autoresume all videos/channels by default?
Which line(s) in your script do I have to change in order to hide the activate/deactivate option button?