You can do that by modifying the Firefox desktop shortcut and add the URLs to the target line. Use the -new-window command line switch to open URLs in a new window. You may have to use a CMD file with the start command (start "" "path-to-firefox\firefox.exe") if you exceed the maximum length of the target line. *"path-to-firefox\firefox.exe" url1 url2 -new-window url3 url4 -new-window url5 url6 See: *https://developer.mozilla.org/Command_Line_Options