Bye World Cup.
This extension will remove all tweets on your Twitter feed that contain the words "World Cup". It is case insensitive, and spaces do not matter. EG tweets containing the words "World Cup", "WoRlD CuP", "#WorldCup" and "worldcup" would all be removed. I made this as I dislike football, and was becoming increasingly annoyed by the quantity of football-related tweets that were finding their way onto my feed.