Are there policies/guidelines regarding the use of third-party icons in software maintained on WMF's Gerrit instance (e.g. MediaWiki extensions)? For example, the Chameleon https://www.mediawiki.org/wiki/Skin:Chameleon skin appears to use Glyphicons http://glyphicons.com, whose license http://glyphicons.com/license/ is not very clear. Even if it uses them as part of the Twitter Bootstrap, is it legal/fair to embed a piece of software (Glyphicons) that cannot be used freely without another piece (Bootstrap)? Even git.wikimedia.org https://git.wikimedia.org uses Glyphicons (the free PNG version) without complying with the CC-BY 3.0 license.
Wouldn't it be better to use a really /free/ icon set (such as Font-Awesome https://fortawesome.github.io/Font-Awesome/ or Elusive Icons http://shoestrap.org/downloads/elusive-icons-webfont/) instead?