I use firefox for all my internet browsing, and I really like it, except one thing. 80% of the extensions that I have loaded all break everytime I upgrade to the next version, and I have to go and re-download them and install them again, and set up and settings they have. What a PITA. You think that extension developers would get a delta document or something so they could have the extensions ready to go when the next release of the browser comes out. It would also be nice for firefox to tell me what extensions will break before I install the newest version.
Adblock is about the only one that always works. Tabbrowser pref’s always breaks which makes browsing alot harder for a week or two after upgrades. The tabbrowser extension allows you to open everything in a new tab. When it breaks, everything opens up in a new window, so you end up having 8 browsers open, like when you surf with IE.