Jeff is using colors to highlight specific text by audience in https://developer-new.mozilla.org/en-US/docs/Localization_Quick_Start_Guide, and they're not shown in the kuma version of MDN. Probably similar to bug 769570?
I've done a Github's PR adding the color CSS property to the CSS whitelist for the style attribute. ( https://github.com/mozilla/kuma/pull/402 ) Once merged, this should fix the problem. Note that in the mid-term we plan not to use the style attribute anymore, but to replace it by semantic class attributes (which will let us to centrally control the chosen color for example). But that's for the mid-term future.
Commit pushed to master at https://github.com/mozilla/kuma https://github.com/mozilla/kuma/commit/dcc6b63a9ace4b8488f7b84f426c65a22c972dbf fix bug 773923: Whitelist 'color' in style attributes.