Forum zgromaźeństwa Firefox

I HAVE TRIED TO FIND A STREAMLINED WAY TO DELETE MULTIPLE DUPLICATE BOOKMARKS (UNINTENTIONALLY CREATED BY AN OLDER FIREFOX BOOKMARKS IMPORT). BUT I HAVEN'T FOUND ANYTHING THAT WORKS. USING BOOKMARK MANAGER IS FAR TOO TEDIOUS AND TIME-CONSUMING. AND AN EXTENSION ADD-ON I TRIED CREATED EVEN MORE PROBLEMS. I NEED HELP!!

I am used to having a Firefox for my personal Mozilla account, bookmarks and sessions, and Firefox Developer Edition to be logged in my work account, where I could use everything I need to work in a separate environment.

Recently I changed a job. Logged out past-job@mail.com from Firefox Developer Edition, logged in with present-job@mail.com and... I still can see old bookmarks.

- I cleared history and new bookmarks: nothing
- went to about:preferences#privacy and clear all the data: bookmarks still there
- tried Help > More troubleshooting information > Refresh Firefox…: all the same
- reinstalled firefox@developer-edition with brew: nah
- eventually, logged out from presetn-job@mail.com in Firefox Developer Edition and personal@mail.com in Firefox; uninstalled both, deleted everything related to "mozilla" and "firefox" was able to find in my system: unsuccessfully

The last thing I didn't try yet is burning my laptop in favor to a new one.

Where are those bookmarks? Why nothing is helping?