# Firefox 4 and MathJax \not

I'm currently using Firefox 4.0 on OS X, with STIX fonts installed, and for some reason MathJax (in HTML-CSS mode) is not rendering the \not symbol at all, i.e. for me $a \not = b$ looks like $a = b$ rather than $a \ne b$. This rendering problem seems to be limited to StackExchange; I don't have any problems on MathOverflow. Chrome and Safari also render \not correctly.

• I experience similar problems with FF 4.08 (I think) that I installed in my office computer (on windows XP), all the TeX fonts look extra-crummy. I do recall, however, that there's no official support to beta browsers... so I'm still waiting until FF 4 comes out officially before I complain :-) – Asaf Karagila Jan 16 '11 at 14:38
• On Firefox 4, to get decent math display, I have to right-click on a piece of math, go to Settings->Math Renderer and pick "MathML". With "HTML/CSS" the output is very bad. That being said, there is certainly some problem with the "not" symbol. It isn't placed correctly, and if I switch rendering modes from MathML to HTML and back, it doesn't end up in the same place it was. It ends up on the far left end of the = sign. – Carl Mummert Mar 22 '11 at 13:34
• I have sometimes seen the problem even on Firefox 3, FWIW. – ShreevatsaR Apr 2 '11 at 7:03

## 1 Answer

We do not, as a matter of policy, support beta browsers. Feel free to ping me on this answer if the problem persistes after FF4 is released.

• FF4 has been released, and the problem persists. I think the problem is with overlaid symbols in general. – Zhen Lin Mar 22 '11 at 12:38
• @Zhen: please also see this thread. meta.math.stackexchange.com/questions/1737/… – Willie Wong Mar 23 '11 at 16:05
• It's one thing not to support a pre-release browser, but it's another to completely ignore it. Indeed, one of the main purposes of releasing builds of the browser before it's done is so web developers can fix pages broken by the new version before it's released to hundreds of millions of users. – Justin L. Mar 25 '11 at 18:29