User Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.2) Gecko/20100101 Firefox/6.0.2 Build ID: 20110902133214 Steps to reproduce: I wanted to uninstall the inactive add-ons from the list which are marked as "incompatible" with the current Firefox version. Actual results: The incompatible items don't have a "uninstall" or "remove" button. Restarting Firefox in "Safe mode" without add-ons didn't help, in contrast to the advice here: http://kb.mozillazine.org/Uninstalling_extensions http://support.mozilla.com/en-US/kb/Cannot%20uninstall%20an%20add-on it Expected results: Inactive add-ons should either be removable or kept invisible (filtered) from the add-ons list. Tidying up the Windows registry or program folders may solve the problem but is inconvenient and possible risky (deleting the wrong things).

Firefox didn't install those addons in the system and can't therefore uninstall those addons. To uninstall those addons use the uninstaller from that software that installed them in the first place.

OK, I understand that. Even so, IMHO it would be helpful if Firefox could a) show a message in the add-on list, that add-on XY is not only incompatible and must uninstalled externally and/or b) optically hide or filter those add-ons from the list, e.g. with a checkbox or toggle button.