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Adds a new button next to like that quick adds / removes the active video from your "Watch later" playlist
< Feedback on YouTube - Add Watch Later Button
Same here, it doesn't work in Firefox.
It works on Firefox 129.0.2 (64-bit) with Tampermoneky 5.1.1. Both are the latest versions.
It is silly that each different userscript extension has an incompatible API. Is there some wrapper script to make it interoperable?
I don't know, since I only work with Tampermonkey.
The button shows up, and the icon toggles when you click it, but it doesn't actually add or remove from the WL list.
Error in the console says "playlistSaveButton is undefined"
This is in Firefox with Violentmonkey. (Doesn't work at all in Firemonkey, btw)