Your scrobbler might have decided to scrobble every song hundreds of times, and you can't really remove those scrobbles efficiently. Or you might have accidentally installed multiple scrobbler extensions at the same time - wondering why multiple scrobbles appear for every song played at a time - and you want to clear them after finding the issue.
Using this script still doesn't necessarily make the process quick since Last.fm only displays a limited number of scrobbles that can be removed on each page of your library. However unlike the implementation of @sk22 and its forks, this UserScript, which is derived from those scripts, is run once. The rest of the process is automated and the script will stop at the page you have set using the prompt.
