Hi, lets start here:

Profile Manager Page

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

This page should list at least two profiles, each with two folders

The profile that Firefox is currently using will have this:

This is the profile in use and it cannot be deleted.

Don't mess with that one.

Option A: Try Launching Other Profiles

Since you are running the latest release, you should be able to use the Launch profile in new browser button for any other profile on the page. But this will update them so older versions of Firefox won't want to use them. If you can think of any reason not to do it, let me know.

If you happen to start your main profile and can continue using it, click the Set as default profile button for that profile so Firefox uses it automatically at the next startup.

If you open one that isn't useful, simply close that new window and try any others available on the page.

Success?

Option B: Grab a Bookmark Backup

If Firefox won't let you run a profile, try this:

Find its "Root Directory" line and click the "Open Folder" button. Double-click into the bookmarkbackups' folder and check the date/time coded into the file names. The name also shows the number of items in the file, for example:

bookmarks-2020-10-20_2732_gibberish==.jsonlz4

To ease the process of using the file, I suggest right-clicking one you want to use and choosing Copy. Then right-click on the Windows desktop and choose Paste.

Back in Firefox, open the Library window and use Restore to apply those bookmarks to your current setup (you'll use Choose File... and point Firefox to the file you pasted on the desktop): Restore bookmarks from backup or move them to another computer.

Any luck?

So close-had 3 profiles..one of them had all my bookmarks!! but when i went back and marked that one as default and relaunched-bookmarks were gone..

went back to profile page-launched in new browser and they r there...must have misunderstood instructions..have correct profile open on laptop-how can i get Moz to use this? thought setting as Default would do it-but it didn't.

worried about going forward if unclear...

or is option bc i found them in old profile i should try the import option?

Can't thank u enough..

WOW so close-I see them!! Ok had 3 profiles-1 default & 2 others..used the launch profile in new browser and FOUND them.

However when i went back to profiles & set THAT profile to default and opened Moz bookmarks were gone again. Went back at launched profile in new browser-there they are.

I guess I don't understand next step. Have them open now on screen again-should I have set this profile as default? if yes, why didn't it work? Bookmarks only show if I launch in new browser. Shouldn't I be able to set that profile as default and they stay attached? Or is answer using the import/export option to move into original default profile?

you are amazing..almost there..

IT WORKED!!!! followed the instructions to find, copy, and restore bookmarks from previous profile to new default. Sure bookmarks seem like a silly thing to be worried about-but I can't thank you enough.

Thank you so very much-

A default-release.xxxxxxxx profile is the preferred profile for current Firefox releases. If the profile that has the bookmarks is named differently then best is to keep using the default-release.xxxxxxxx profile and transfer the bookmarks to this profile.

You can copy certain files with Firefox closed to the current profile folder to transfer or recover personal data. Note that best is to avoid copying a full profile folder.

• bookmarks and history: places.sqlite
• favicons: favicons.sqlite
• bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
• cookies.sqlite for the Cookies
• formhistory.sqlite for saved autocomplete Form Data
• logins.json (encrypted logins;32+) and key4.db (decryption key;58+) for Passwords saved in the Password Manager
  key3.db support ended in 73+; to use key3.db in 58-72, make sure to remove key4.db
• cert9.db (58+) for (intermediate) certificates stored in the Certificate Manager
• persdict.dat for words added to the spell checker dictionary
• permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
• sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)

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
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

thank you as well for taking the time and sending a great response. I was able to restore bookmarks from previous profile to default. Thanks again