Firefox Bookmarks Disappear (Lost)

It was the 3rd time in as many months. Firefox 'lost' its bookmarks. Had to go through the profiles and retrieve from the backup folder. That (referring to Firefox) was shitty. Even though I reinstated the bookmarks from the backup folder, I still had to rearrange my toolbar filder since it overlaps and I can't delete the default toolbar folder in Bookmarks. So, I had to drag the ones I had (the ones I should have!) into the new empty default folder.

Stupid Firefox. How can you lose you're bookmarks?