Totally agree. It's not the fault of Firefox at all. This is just being trigger-happy on new standards before they are ready and unwillingness to fix a problem in a different way.

It got added because it worked extremely well on browsers that implemented it, and it solved a problem that was needed on the site in question, which was very difficult to solve otherwise. I can't blame a site for using an open standard that works for a majority of its users and which makes the development effort significantly less.