Updating fedora core 3
See Problematic extensions and Firefox crashes#Extensions for more information.
Depending on your browser version and OS, Firefox or Sea Monkey may hang, crash, or simply fail to start because of a problematic plugin.
If possible, visit Mozilla's Plugin Check page with another browser that Plugin Check supports (e.g., Safari or Opera) to help identify installed plugins.
 Update all plugins, uninstall any plugins you no longer need or disable all plugins, to see if that resolves the problem.
 As a workaround, open the Firefox installation directory (usually C:\Program Files\Mozilla Firefox) and look for two "js3250.dll" files (the second one will be named "js3250moz-backup").This error is caused by inconsistent file versions ("application.ini" and/or "platform.ini" and possibly others).The problem may be a security program such as Zone Alarm Extreme Security (see below) that is preventing changes to your Mozilla application files after an update. Firefox may fail to start if the Iolo System Mechanic application is installed.You may see an error message similar to: - Application Error. Internet Explorer, Google Chrome, or other browsers may also fail to start.