Currently Firefox doesn’t let you modify any tabs. Please follow the discussion here: https://www.addongenie.com/forums/topic/colorfultabs-disabled-in-firefox-quantum
Legacy AddOns fixed to work on current versions of Firefox and lots of awesome goodies!
Currently Firefox doesn’t let you modify any tabs. Please follow the discussion here: https://www.addongenie.com/forums/topic/colorfultabs-disabled-in-firefox-quantum