Hmm, still seems kinda messy to rely on CSS.

Next thought, maybe you can override Google's open method with something like this: http://jsfiddle.net/Z3Ysq/

They may have been able to prevent this with a closure, but I think you could workaround everything. Watch out for scope issues, but I think there's a way to make this completely generalizable.

That being said, I agree that at some point, it might get too messy figuring this all out that your existing solution is best. Kudos for the clever concept.

You look at Gmail's JS and tell me which function is the "open compose" :)

Someone who can do that would get hired pretty quickly!