I saw this Math question (now deleted) in the Hot Network Questions:
(This screenshot is of the stackexchange.com Hot Questions list.)
The title is also illegible on all sites when it appears in the HNQ sidebar, including the Math site.
Last time I checked, questions that use MathJax in the title should not become hot, but I think what's messing it up is the fact that it uses \begin{equation*}
instead of the standard delimiters (i.e. $
or \$
). Note that the MathJax renders properly in the title.