Gravydog316 macrumors 6502a Jan 30, 2019 #2 type "about:config" in your menu bar, look for "app.update.doorhanger", double click to change 'Value' from True to False, then restart Firefox.
type "about:config" in your menu bar, look for "app.update.doorhanger", double click to change 'Value' from True to False, then restart Firefox.