It is possible for add-ons to hook into the uninstall event and disable event, then cancel the requested uninstall/disable action preventing users from disabling or removing the add-on. This can be used by malicious add-ons to "inform" the user that the add-on is hijacking the browser for their "benefit" (via popup) then prevent the user from removing the add-on. This is now being used by Conduit add-ons (note: they are not preventing the uninstall, just displaying a popup which prevents removal/disable unless you hit OK). Examples: Bug 902569 and Bug 902578. Expected Results: Add-ons can be disabled or removed as requested by the user. Actual Results: Add-ons can be disabled or removed only if permitted by the add-on.
Wesley can you still reproduce this issue? If so please provide the addon and it's version.
The 2 bugs listed in comment 0 have attached add-ons which will prevent removal of the add-on unless you hit the OK button. I will see if I can create a reduced test case.
Created attachment 796713 [details] Proof of Concept addon This is a proof of concept that demonstrates preventing the add-on from being disabled or uninstalled. If you click disable nothing happens. If you click remove, a warning message is displayed, and the add-on is not removed. The only way to remove the add-on is to delete it from the extensions folder. This was tested on the latest Nightly 26.0a1 (2013-08-28).