It's coming. There's a spec here: http://dvcs.w3.org/hg/webevents/raw-file/default/mouse-lock.html http://dvcs.w3.org/hg/webevents/raw-file/default/mouse-lock.

It's coming. There's a spec here: http://dvcs.w3.org/hg/webevents/raw-file/default/mouse-lock.html http://dvcs.w3.org/hg/webevents/raw-file/default/mouse-lock.... Implementations for Chrome and Firefox are bug 72754 and bug 633602, respectively.