Also, recently, whenever I have to use Windows Task Manager to close out Firefox, instead of getting a message saying "This program is waiting for a response from you" which I can click out of, close completely, then re-open with all my tabs saved in the Restore Session feature, whenever I use WTM now, it completely wipes out my tabs and instead of giving me my tabs back, it instead just gives me a session to restore from more than a few days ago. I have tried clearing my history, and nothing has helped.

You can check for problems with the sessionstore.js file in the Firefox profile folder that store session data.

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Multiple_profile_files_created

Deleting sessionstore.js will cause App Tabs and Tab Groups and open and closed (undo) tabs to get lost and you will have to recreate them (make a note or bookmark them if possible).

You can also check the backups in the sessionstore-backups folder.

You can use this button to go to the currently used Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox