Try to repair the disk permissions:

• http://thexlab.com/faqs/repairprocess.html

Try to remove the Firefox plist file (org.mozilla.firefox.plist).

• http://www.macfixit.com/article.php?story=20060606082246983 How .plist files become corrupt and troubleshooting the results

Go to "Library > Preferences" and remove the plist file for Firefox (org.mozilla.firefox.plist).

Thanks for the suggestions. Repaired disk permissions (well, super-duper did before my last backup) and no effect. The plist idea was interesting, but there was no org.mozilla.firefox.plist in library preferences, so tried the appzapper which found it and supposedly removed it, but still no change... Aargh.

Thanks again....

Try to uninstall (trash) and reinstall Firefox.

Download a new copy of the Firefox program and save the disk image (dmg) file to the desktop

• Firefox 8.0.x: http://www.mozilla.com/en-US/firefox/all.html

• Trash the current Firefox application to do a clean (re-)install
• Install the new version that you have downloaded

Your profile data is stored elsewhere in the Firefox Profile Folder, so you won't lose your bookmarks and other personal data if you uninstall and (re)install Firefox.

• http://kb.mozillazine.org/Profile_folder_-_Firefox

Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

• https://support.mozilla.com/kb/Basic+Troubleshooting#w_8-make-a-new-profile

If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Creating a new profile seems to have resolved the problem. Thanks!