User blog comment:Kirkburn/Technical Update: August 31, 2016/@comment-26402117-20160901131645/@comment-24473195-20160901143624

>Okay, so in terms of this feature (which is what I meant, I guess not clearly enough), what do orange and blue mean?

Blue means added content, orange means removed content. I googled a bit and  found these (beware wall of text):


 * https://phabricator.wikimedia.org/T13374


 * https://phabricator.wikimedia.org/T121469#1887032


 * https://phabricator.wikimedia.org/T35335

"To me, I'm not seeing constructive meaning in including them (red and green seem to have a more obvious relationship to this content)."

Accessibility is the main concern. That being said, you are free to choose whichever colors you like using personal css.

One size does not fit all in this specific scenario.