tip for troubleshooting Firefox addon problems

There seems to be a conflict between Google Toolbar addon and Firefox Personnas addon, and some other extensions in Firefox.

The solution is to start up Firefox in "safe" mode and disable or uninstall the addons.  I did this and it worked for me.  Until then, some parts of Firefox were not working - including the Addons manager.  Plus, I was getting error messages at start up time and some runaway script messages during use.

All of the problems have now been solved.  Hope this helps someone.

Starting Firefox in "safe" mode is very easy on the Macintosh, by the way.  Simply hold down the Option key on your keyboard while launching Firefox.