I had no idea this was an issue until reading about it recently. Thanks so much for this extension, appears to be working based on the test page. Hopefully I'll never find a website compromised and using CSS in this manner, however, at least I will have a number sign to show how many and also protection against it.
Thanks for that!
Also, I haven't found the compiled version for Chrome, is it on the chrome store? My friend uses chrome, thanks.