Oh, I’ve run into this before too — it’s super frustrating when bookmarks lose their URLs like that. Usually it happens if there’s some corruption in the bookmark backup or syncing issues across devices. Restoring an older backup works, but it’s definitely annoying to do multiple times a month.

I’ve seen similar quirks even on platforms like phonexa, where keeping data organized and synced properly can prevent small issues from turning into bigger headaches. Bookmark management in Firefox seems to need the same kind of careful handling.

If it happens again then try this test.

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 in "Help -> More Troubleshooting Information" (about:support)

If errors are reported with "Verify Integrity", close and restart Firefox or reboot the computer and retry.