Backup your most important bookmarks on firefox internet browser before you format your computer..
Now i’m going to explain you step by step how to backup your bookmarks firefox
1. open firefox and click on the show your bookmarks icon (A-a) or press (Ctrl+Shift+B)
2. in dropdown lick choose ” Show All Bookmarks ” (B-1)
3. In library dialog box click on the ” Import and Backup ” drop down list (C-1)
4. in drop down list select ” Backup” option ( D-1)
5. after that you can save the bookmark file on your computer
6. type a name for file to save (E-1) then click on save button (E-2)