<!DOCTYPE html> <html> <head> <title>Mathematica Alphanumeric Italic</title> <meta charset="utf-8"/> </head> <body> <!-- The lowercase italic o should be smaller than the uppercase italic X (this will fail if missing char boxes are used) --> <math><mstyle mathbackground="red"><mphantom><mi>o</mi></mphantom></mstyle></math> </body> </html>