yahoo/pure — pull request #377 by SelenIT (2014-09-05 23:36:21+00:00)
Title: Use Flexbox when browser @supports it unprefixed

Don't discriminate Firefox 28+ which supports Flexbox unprefixed (including flex-wrap). We can use unprefixed Flexbox as a main layout mechanism (for all modern browsers), prefixed Flexbox implementations as a fallback and inline-blocks as a last resort.