While TenFourFox had made it much tougher to add new addons to the browser, with the ending of the XUL frameworks, older Firefox-based addons need to run, it will not disable any auto-updating you already have in place. Am starting to run into updates that break functionality. Videodownload helper just auto-updated this morning and stopped working. You have to uninstall it, and then re-add version 6.3.1 (last version that will work for us), and then make sure auto-updating is disabled. Is reasonably current and should continue working for a while.

Others too like "Google Search Fix", that removes search-tracking no-longer works in Yahoo, but still does in Google searches.

Fortunately, Cameron Kaiser is modding the browser to accomplish many of the same things that these addons did, but if you have one you are very fond of, is worth locking it down before it stops working.