I saw this set of
Firefox Pranks last night and thought I'd install them as an April Fool's prank for the wife. After installing the extension, I tested it by going to YouTube and confirming that Rick Astley was coming up for a bunch of the links.
About ten minutes later, I felt guilty and uninstalled the extension. I tried YouTube again, but Astley kept coming back. I tried the Extension Manager, the properties file, everything! No luck. I ended up fifteen minutes late for work, nearly missing my first meeting, and expecting to completely uninstall and reinstall her browser when I got home tonight.
Then I found out that YouTube itself had replaced most of their front page videos with Rick Astley clips. The browser was fine, it was the internet that was conspiring against me. Stupid jerks.