[mrspeaker]

For the non-clickers: It's Webkit, not Firefox that it will be disguising itself as:

"The 'like Gecko' string has been part of most WebKit-browser UA strings from time immemorial, but has never been used by Firefox, which instead uses 'Gecko'".

[Millennium]

The first versions of Safari had "like Gecko," so its WebKit heritage is long indeed. Maybe MSIE should use "sort of like Gecko" instead?