About the only thing else I can think of is a clean uninstall of Firefox. That includes deleting your passwords and Bookmarks. You can save
your Bookmarks before uninstalling. I save passwords by taking screen shots of them. To save bookmarks click on Bookmarks and choose
Show All Bookmarks. Choose Import and Backup. Export Bookmarks to HTML and save on your Desktop.
Run the Firefox uninstaller. Then click on Start and enter Firefox in the Search Box. Delete all the files found. Run another search using Mozilla. Delete
all the files found. That will remove your Firefox profile.
Download Firefox from Download Firefox — Free Web Browser — Mozilla