Topic: State of Action Sheets?

Somebody recently said "action sheet", so I went looking around. I only found a few things -- W3C being one of them, but that's straight forward tech stuff (that I've read so far).

I'm curious about the state of action sheets. Proposal? Recommendation? Browser concerns? Safe to implement? I'm curious about things along these lines.

The poster has demanded we remove all his contributions, less he takes legal action.
We have done so.
Now Tyberius Prime expects him to start complaining that we removed his 'free speech' since this message will replace all of his posts, past and future.
Don't follow his example - seek real life help first.

Thanks, InI. One of the better discussions I've read so far.