Can anyone confirm whether final flexbox support was added? http://caniuse.com/flexbox suggests that FF 18 only has support for the old version of the standard.
As referenced from Mozilla[1], Firefox and Opera support the new spec without prefix, Chrome supports it with the -webkit prefix, and Internet Explorer supports the old-flexbox.
That page says it's behind a developer flag, and only limited single-line support is provided. Is the page up to date, or is the feature fully implemented, and accessible to anyone, regardless of flags?
Firefox 20 will contain css3 flexbox unpreffed and unprefixed. Assuming nothing is found that would make us flip the pref to false during the Aurora or Beta cycles.
The page is up-to-date.
According to the channel on freenode, full, up-to-date, and prefix-free flexbox support is on track to be enabled in the stable version of Firefox that is released exactly 12 weeks from tomorrow.