Hi Mary Did this started recently or longer ago? Are you using Sync to sync the bookmarks? If you use Sync then best is to disconnect Sync while performing maintenance/repair efforts to files in the Firefox profile folder. You can check for problems with the <b>places.sqlite</b> database (bookmarks and history) in the Firefox profile folder. *https://addons.mozilla.org/firefox/addon/places-maintenance/ See also: *http://kb.mozillazine.org/Bookmarks_history_and_toolbar_buttons_not_working_-_Firefox *https://support.mozilla.org/en-US/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file If you see a sudden rise in the number of bookmarks as reported in the name of automatically created compressed .jsonlz4 backups then you can try to restore an older copy with a count that looks more as it should be. *Bookmarks -> Show All Bookmarks -> Import & Backup -> Restore The name of a JSON bookmarks backup file includes a total item count (folders and separators included) and an hash value to prevent saving the same backup more than once. *bookmarks-YYYY-MM-DD_<item count>_<hash>.jsonlz4.