Created attachment 193153 [details] testcase This is an old bug, I'm not sure it is still valid but that was reported by Chrome users on Windows XP and Vista. I don't have these Windows versions so I can not verified the bug, but hopefully the attached testcase should allow someone to do so. Basically, we had to add some workarounds in MathJax to remap the characters to other code points as well as using a separate WinChrome font. That would be great if we could get rid of that. In the first set of characters from the attachment, each line has two chars (one from a MathJax font and one from the WinChrome font) that should match. In the second set of characters, the combining characters should be visible. That was not the case on old version of Chrome. See also: https://github.com/mathjax/MathJax/issues/239 https://github.com/mathjax/MathJax/issues/202
I'm getting the undefined box instead of symbol U+20D7. But does it really has to be displayed? As I understand from the comment, the symbol U+20D7 was replaced by U+2192: https://github.com/mathjax/MathJax/issues/239#issuecomment-8277906 "...The vector arrow was harder as I had to use the regular right arrow, which is too big. But at least it gets the point across." So now, if I open the page http://www.mathjax.org/demos/tex-samples/ in Chrome, I can see the big arrows (U+2192) in place of vectors (Maxwell’s Equations section). And if I open the same page in FireFox or Opera, I can see the small arrows U+20D7 on the same place.
Yes, we had to replace the small arrows by a big arrows in Chrome, exactly to workaround that issue. We also have to use special fonts to workaround other issues with missing characters. As Davide indicated on the MathJax tracker, the code points that have the issue seem to change from version to version. Someone recently reported a similar issue again: https://groups.google.com/forum/?fromgroups=#!topic/mathjax-users/N80lpcf9wVM