This is an extension I'd use once in 5 years. Boy am I glad this exists when that time comes.

What this does:
1) You must be logged-in to your youtube channel
2) This must be added on your browser bar
3) Click on it
4) Click on the button to take you to your watch later list
5) Click on the button to clearn

This will automate removing videos from top to bottom. Go away for a bit and run it again.

this add is the one I really need

Works like a charm! Thank you!
Little update:
As i understand everything is fine but add-on can't delete hidden videos.

works great

I was dreading the thought of going through thousands of videos to remove them from my watch later playlist myself, so glad I stumbled onto this extension lol. It works perfectly, thank you!

worked perfectly. thank you.

It's kinda wonky, initially it wouldn't initiate but if you spam refresh or use another extension to "trigger" it, it'll start working and it's REALLY fast, it took like 10-ish minutes to wipe 600 videos from my watch later

Worked perfectly. Deleted every single one of the almost 5k videos i had.

does exactly what it claims to do, simply, and easily.

Literally does nothing after hitting the button

Works perfectly fine in my case

It works again! I don't know what happened, but it worked when I first installed it a few months ago, then all last week it did nothing. Suddenly tonight it's working again. I think this time I invoked the cleaner from the Watch Later list after I had played one video,(the list gets narrower) then a window popped up to let it navigate to my Watch Later list, THEN it worked properly.

I don't get it. It doesn't say anywhere what it's going to do. It has a button that says start cleaning, but it doesn't say what cleaning does, does it delete them? Which ones does it leave? How do I leave recently added ones? How do I move others to a different playlist? Nothing is explained.

Work as per its name. Brilliant extension. I have used some other extensions also but they break process if you switch to other work, but it continue to do its task.
I request the developer to add a option of removing Liked videos also.

Does work, but says it can't find the option to show unavailable videos, so you may want to enable it manually before you use this extension. Once it also glitched out and started queuing videos instead of deleting them, this was fixed by reloading the page and running the cleanup again

Works as expected

works

Does what it needs to do, thank you :)

The only currently working tool I could find for this issue. It is P A I N F U L L Y S L O W however, any more then 500-1000 videos would take hours (based on my experience).