I have been a loyal FF user since the very beginning and as an IT consultant have switched hundreds of client over to it. This FF6 is an abomination. None of my Add-Ons are compatible with it, causing "TypeError: Components.classes[cid] is undefined". I just sent a link for a youtube training video to my clients and it was pointed out that FF6 will not recognize it (Chrome and IE do). "Enter" does not work when going to a site via address bar. The worst part is if you try to use an older version of FF it will relentlessly ask you to "upgrade" to 6. Now I am having to scramble to get Chrome to all my clients to save face after insisting on their switch to FF all these years. I can't believe that FF doesn't come with a "revert to previous edition" just in case of a huge mess up like 6.