User-Agent: Mozilla/5.0 (Windows; Windows NT 6.1; WOW64; sk; rv:2.0b2pre) Gecko/20100707 Minefield/4.0b2pre Build Identifier: Mozilla/5.0 (Windows; Windows NT 6.1; WOW64; sk; rv:2.0b2pre) Gecko/20100707 Minefield/4.0b2pre While reading comments under news about release of new FX4 Beta, I noticed that many users were complaining about changes in general. Two main problems they have are: 1. They don't know they can change it back. 2. They don't know how it can be changed back. I think doorhanger notification with text "Would you like to revert the new UI?" would be sufficient. Reproducible: Always
Why don't we tell people that they can "change it back" in the website downloading Firefox 4? We can also have tutorials about Using Firefox 4. In tutorials we can tell them that you can change the theme back to the theme in Firefox 3.6 and how you can do it. Using Doorhanger notification is also a good idea.
See related discussion (URL).
If you want the old theme look, I'm sure someone will make a theme package. For individual pieces of UI functionality (like tabs on top), you can switch these back. For infrastructure issues (say, if you wanted to go from the doorhanger notifications back to the old notification bars), that's unlikely to happen.