some of my bookmarks switched to grey globe overnight and no longer work. they were not imported from any other internet browser and were working the night before.
Try rebooting the computer.
If you use Sync then best is to disconnect Sync temporarily during troubleshooting.
This can be caused by a problem with the places.sqlite and favicons.sqlite databases in the Firefox profile folder.
- use "Verify Integrity" button on the "Help -> Troubleshooting Information" (about:support) page
If errors are reported with "Verify Integrity", close and restart Firefox or reboot and retry.
If "Verify Integrity" cannot repair places.sqlite, rename/remove all places.sqlite and favicons.sqlite files in the Firefox profile folder with Firefox closed. Firefox will rebuild places.sqlite and restore the bookmarks from a recent JSON backup in the bookmarkbackups folder.
- keep a backup copy of places.sqlite in case a new places.sqlite database has to be created
You lose the history when a new places.sqlite is created.
You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.
- Help -> Troubleshooting Information -> Profile Folder/Directory:
Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder