You can customize Firefox 4 to make it look and behave like Firefox 3.6, for details see http://redherring2.wordpress.com/2011/01/17/firefox-4-restoring-firefox-3-ui

If it is something else you don't like, tell us and somebody may be able to help you, Firefox is very customizable.

It is best not to go back to Firefox 3.5 as you will lose data (history and cookies), you can go back to Firefox 3.6.

To downgrade to Firefox 3.6.* you can uninstall Firefox 4, but do not select the option to "Remove my Firefox personal data". If you select that option it will delete your bookmarks, passwords and other user data.

You can then install Firefox 3.6.* available from http://www.mozilla.com/en-US/firefox/all-older.html - it will automatically use your current bookmarks, passwords etc.

To avoid possible problems with downgrading, I recommend going to your profile folder and deleting the following files if they exist - extensions.cache, extensions.rdf, extensions.ini, extensions.sqlite and localstore.rdf. Deleting these files will force Firefox to rebuild the list of installed extensions, checking their compatibility, and reset toolbar customizations.

For details of how to find your profile folder see https://support.mozilla.com/kb/Profiles

Thank you very much. As of right now I am ok and will stay with the newer version

The only feature I see that I might have some troubles with is the one Switch To Tabs Manager (or whatever it's called). Since it's so easy to get distracted on Facebook, I usually open a tab for my homepage, one for each email message, and one for each notification, then deal with everything in my own time. I've not attempted this yet in the new FireFox, but can anticipate it being a problem if I keep trying to open a new tab & keep getting taken back to the screen I have open. If it turns out to be a problem I will try the address above to restore FF 3.6 settings; is there other advice you could give on this issue?

Thanks so much for answering. Like I said, I am ok now and am getting along ok.

Xmarks or Firefox Sync add-ons. These will save everything for your transition.

Thanks for the info. It's a big help.

So rather then answering the question, you say, "get over it".

I WANT TO GO BACK TO VER 3.5.

I am OK with loosing all my stuff from Ver 4.

Ver 4 DOESN'T WORK. IT DOESN'T CONNECT TO THE INTERNET.

Neither does Ver 3.6.

So, HOW DO I GO BACK TO VER 5?????

Thanks.