With firefox 85.0.1-1, my extensions installed from Debian repositories are no longer disabled on launch.
I made sure to restart Firefox several times to not get tricked by the temporary normal behaviour right after a firefox update. I browsed a couple Web pages too, to check that the add-ons are actually working and not merely showing as active. - firefox 85.0.1-1 - webext-ublock-origin-firefox 1.32.0+dfsg-1 - webext-umatrix 1.4.0+dfsg-1
OpenPGP_signature
Description: OpenPGP digital signature
