I do this as well i.e delete the name of a bookmark using only it's favicon to identify it. When you login to Firefox. Just right click your bookmarks and hit

I do this as well i.e delete the name of a bookmark using only it's favicon to identify it. When you login to Firefox. Just right click your bookmarks and hit open all in new tabs. It will open all 500+ tabs. Leave it for a few minutes all all the favicons will be loaded.