Please enable the AMSsymbols extensionfor MathJax. The lack of this extension has led to several independent bug reports.
- The \not\mid symbol is not working well
- Tex \implies symbol does not work
- TeX beth symbol missing
More independent bug reports (everyone, please feel free to add them if/when you can edit this post):
[status-bydesign]. So far this is clearly by-design as extensions are not turned on before we request it. A feature-request is some desired outcome that (most of) you want to be. A feature-request doesn't mean it is less important than a bug. $\endgroup$
[tex]tag should be sufficient. $\endgroup$