Newer version of FireFox27.0.1 with about:config tweaks recently needed. The previous version was Aug. 2016... a lot has happened since. This version, like previous versions, is installed in /root, then unpacked from there. Any links on Desktop must be to /.mozilla/firefox/firefox for correct link. This is a "modular" approach, if it doesn't work, just remove this .mozilla file, and the .cache/mozilla folder. Thats it. Of course, make a backup of your browser and any bookmarks.
There are some small addons for conveinience, the largest is FireFTP, this can be removed. I don't recommend removing AdBlock Edge, its been shrunk a lot, and will update once a day. Compared to other solutions, it is small and does not grow much at all.