Firefox is highly customizable and you may be able to customize it to meet your needs.

If you do not like the new UI, you can make Firefox 4 look and behave more 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, what do you want to change?

To downgrade to Firefox 3.6 first 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 the latest version of 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

http://www.mozilla.com/en-US/firefox/all-older.html

The best way to do this would probably be to install 3.6.16 right over 4.0 so that you can ensure that all your favorites and history are kept.

Note that once you downgrade back, the Refresh, Cancel, and possibly Home buttons will still be to the right of the URL bar. You can move them back by right clicking on the area with them and choosing "Customize...". Then you can drag them back over to the left.

It is better to uninstall Firefox 4 then re-install Firefox 3.6.15 to ensure that no remnants of the Firefox 4 application are left behind.

I followed directions to uninstall 4.o and went to the install 3.6 install page and the 4.0 install pops up on screen. I have uninstalled all firefox on my Mac and wish to have Firefox installed but not able to understand how. System is 10.5.8. I reinstalled 4.o but to no avail. Not supported on this architecture. ????Huh!!

rkdaly, Firefox 4 requires at least OS X 10.5 and an Intel Mac. There is a third party version of Firefox 4 that runs on OS X 10.4/10.5 and PPC Macs, for details see http://www.floodgap.com/software/tenfourfox

rkdaly's issue seems to be a bit more than that. He says he was on the download page for 3.6 and the installer for 4.0 came up.

rkdaly, you may wish to ask your own problem about this so you can better describe the issue.

I am a new computer user and None of the above makes any sense to me. I would like to uninstall firefox 4 aqnd reinstall 3.5. Can anyone tell me how to do this? please remember I have limited knowledge about computers