Problems with bookmarks and history not working properly can be caused by a corrupted places.sqlite database file. *http://kb.mozillazine.org/Bookmarks_history_and_toolbar_buttons_not_working_-_Firefox *https://support.mozilla.org/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file You can try to check and repair the places database with this extension: *https://addons.mozilla.org/firefox/addon/places-maintenance/ ---- You can try to find an older copy of the places.sqlite file in the Time Machine or try to restore the bookmarks from a JSON backup in the bookmarkbackups folder. *http://kb.mozillazine.org/Lost_bookmarks You can use this button to go to the Firefox profile folder: *Help > Troubleshooting Information > Profile Directory: Open Containing Folder