v57+ See; https://support.mozilla.org/en-US/kb/use-troubleshooting-information-page-fix-firefox#w_places-database

http://kb.mozillazine.org/Locked_or_damaged_places.sqlite

https://support.mozilla.org/en-US/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file

I don't think the cache size matters, so it's more likely a problem with the database. Try to make backups in both formats now:

• JSON: Restore bookmarks from backup or move them to another computer
• HTML: Export Firefox bookmarks to an HTML file to back up or transfer bookmarks

This may not help with the bookmark issue, but I'll note it:

The highest version of Firefox that can run on MacOS X 10.7 is Firefox 48.0.2, released in August 2016. (releases/48.0.2/mac/en-US/)

However, the most up-to-date from the perspective of security patches was Firefox 45 Extended Support Release 45.9.0esr, released in April 2017. (releases/45.9.0esr/mac/en-US/)

With either of those, if you prefer a different language/locale other than U.S. English, click the .. link on the page and find the one you want in that parent folder and then click into it.

You can check for problems with the places.sqlite database (bookmarks and history) in the Firefox profile folder.

• use "Verify Integrity" on the "Help -> Troubleshooting Information" (about:support) page

See also:

• http://kb.mozillazine.org/Locked_or_damaged_places.sqlite
• https://support.mozilla.org/en-US/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file

If "Verify Integrity" on the "Help -> Troubleshooting Information" (about:support) page can't repair the places.sqlite database then remove all places.sqlite files in the Firefox profile folder with Firefox closed to make Firefox rebuild the places.sqlite database from the most 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
• http://kb.mozillazine.org/Unable_to_process_the_backup_file_-_Firefox

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 Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Thank you for your help FredMcD, jscher2000 and cor-el. -Cmill

Hello,

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