See:

• https://support.mozilla.org/en-US/kb/recover-lost-or-missing-bookmarks
• https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

If you use Sync, best is to disconnect Sync temporarily during troubleshooting.

You can check for problems with the places.sqlite and favicons.sqlite files in the Firefox profile folder.

• use the "Places Database" -> "Verify Integrity" button on the "Help -> More Troubleshooting Information" (about:support)

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 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
• you lose the history when a new places.sqlite is created

You may have to restore an older bookmarks backup in the bookmarkbackups folder via the Bookmarks Manager (Library).

• Bookmarks -> Manage Bookmarks -> Import & Backup -> Restore
• https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them

See also:

• https://support.mozilla.org/en-US/kb/fix-bookmarks-and-history-will-not-be-functional
• https://support.mozilla.org/en-US/kb/cant-add-change-or-save-bookmarks

You can use the button on the "Help -> More Troubleshooting Information" (about:support) to go to the current Firefox profile folder or use the about:profiles page (Root directory).

• Help -> More Troubleshooting Information -> Profile Folder/Directory:
  Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

Months?! Recovery is more difficult after a couple weeks because automatic backups are cycled out. But don't give up yet.

Before erasing anything, could you check how many bookmarks you have right now? One way to do that is call up the Library window (Command+Shift+O as in "Organizer") and then, in the tiny box on the right, search for http and then when the results come up, click the first item, and press Command+A to select all. The count of bookmarks should appear at the bottom. Does this seems to be more than you are finding when you look around manually?

The name of automatically created JSON bookmarks backups in the bookmarkbackups folder includes a total item count (folders and separators included) and an hash value to prevent saving the same backup more than once. You also see this count in the Library Restore menu drop-down list.

• bookmarks-YYYY-MM-DD_<item count>_<hash>.jsonlz4.

If you use the Time Machine or other backup, try to restore file(s) from this backup.

• https://support.apple.com/guide/mac-help/restore-files-mh11422/mac
• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

Months?! Recovery is more difficult after a couple weeks because automatic backups are cycled out. But don't give up yet. Before erasing anything, could you check how many bookmarks you have right now? One way to do that is call up the Library window (Command+Shift+O as in "Organizer") and then, in the tiny box on the right, search for http and then when the results come up, click the first item, and press Command+A to select all. The count of bookmarks should appear at the bottom. Does this seems to be more than you are finding when you look around manually?

I followed your suggestion, and I have 22 bookmarks, which are the ones I've added since I lost the originals.

Sorry guys, I can't follow these suggestions! I'm not good at tinkering under the hood. I try to use Time Machine, but I can't figure out how to find the saved bookmarks. Thanks for trying to help though.

Just out of curiosity, why did I loose them them in the first place?

To clarify the earlier suggestions:

(1) Look at the Restore menu

In the Library window, there is little menu bar and one of the drop-downs has the Restore menu. Each automatic backup has an item count (bookmarks + folders). Do any of them show the larger number you are looking for, or are all of them post-apocalypse?

To get to the Restore menu, see: Restore bookmarks from backup or move them to another computer. That article also has the steps to make a fresh backup "just in case" before restoring any older backups.

(2) Time Machine

I am a Windows person, but my understanding is that when you are in Finder looking at a folder, you can look at Time Machine backups for that folder and see previously saved files.

To get to the folder, see: Profiles - Where Firefox stores your bookmarks, passwords and other user data. Once you launch your profile folder, double-click into the bookmarkbackups folder. Here you'll typically see about a dozen files from the past few weeks. These are named with the date and number of items (along with a gibberish portion).

If you figure out how to look into Time Machine from this point, the older backups also would have the item count in them, so that will help in deciding what to restore. Anything promising there?

Just out of curiosity, why did I loose them them in the first place?

If you don't know, we certainly don't know...

By the way, do you have an Old Firefox Data folder on your Mac desktop? If Firefox's Refresh feature ran at some point, you also would have bookmark backups in there. Of course, no point running it now, this is just looking for another place to recover missing data.

Primary location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• ~/Library/Application Support/Firefox/Profiles/<profile>

In Mac OS X v10.7 and later, the "~/Library" folder in the Home directory is a hidden folder.

• https://www.macworld.co.uk/how-to/mac-software/hidden-files-mac-3520878/

To clarify the earlier suggestions: (1) Look at the Restore menu In the Library window, there is little menu bar and one of the drop-downs has the Restore menu. Each automatic backup has an item count (bookmarks + folders). Do any of them show the larger number you are looking for, or are all of them post-apocalypse?

Thank you! I was able to follow those instructions. February was the pre-apocalypse and I restored that one. All bookmarks are back. Marvelous, thank you. A touch of brain fog earlier trying to make sense of the advice, but I go there in the end.

That's great news. I guess if you don't create new bookmarks too often, the older backups don't get cycled out as quickly as I had thought.