sagemath/sagenb — pull request #205 by ppurka (2014-05-08 09:24:45+00:00)
Title: make \color in MathJax behave similar to \color in LaTeX

Now the following code in a text cell will indeed result in a blue color for the first part.

$${\color{blue} x^2 = x \times x} \text{ not blue }$$