I think all of these also have Chrome versions, but still better on FF due to being able to install (or side-load if not listed or not whitelisted for mobile) onto the mobile version. The day I learned how to get non-whitelisted ones to install and install from xpi was game over for bothering with other mobile browsers.

• FastStream for downloading videos from YT and a lot of other sites (I daily use it for grabbing stuff on Twitter)
• Bypass Paywalls Clean for the obvious (this one is to the dev’s not github but same kind of site site as it has to be installed via xpi)
• Watch on Odysee for seeing if a YT channel also uploads to Odysee to go watch there if possible and at least give my view there
• SponsorBlock for being able to skip hard-coded ads from the uploads and other sections of YT videos
• DeArrow for being able to view titles for YT videos that are more reflective of content
• Wayback Machine for saving pages to Archive.org along with saving them to my account on there.
• Privacy Possum for more aggressive blocking of tracking (though it does require remembering it is on if a site breaks as it will block things that uBO isn’t the cause of the issue)