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Firefox troubleshooting
TroubleshootingIt should not be necessary to create a new profile when you upgrade from a previous version of Firefox providing you do disable all extensions from the prior version before upgrading. To do this, open the old version and open Tools > Options and click the Extensions panel. Click on each of the extensions listed and choose Disable Extension. Click OK to close the Options window. Now it is safe to install Firefox.
Once you have installed Firefox, check to see if there are new versions of all of your extensions that are compatible with the new version, and install them. In the future this process may be automated.
If you enable an extension from an older version of Firebird or Phoenix and it causes problems, run the older version of the browser and disable the extension, then run the newer version again.
If you encounter strange problems relating to bookmarks, downloads, window placement, toolbars, history, or other settings, it is recommended that you try creating a new profile and attempting to reproduce the problem before filing bugs. Create a new profile by running Firefox with the -P command line argument, choose the "Manage Profiles" button and then choose "Create Profile...". Migrate your settings files (Bookmarks, Saved Passwords, etc) over one by one, checking each time to see if the problems resurface. If you do find a particular profile data file is causing a problem, file a bug and attach the file.