The ability (either from the settings page or the toolbar) to enable extensions while in compatibility mode.
After YouTube's crackdown on adblockers, I tried turning off extensions, content blockers, and tracking prevention, but YouTube still detected that there is an ad block.
In compatibility mode, YouTube works all right. what I want to do is to enable compatibility mode, and have extensions like SponsorBlock work.
Maybe something like a "Compatibility mode with extensions" option will do.