Installing the MathML add-on adds a MathML preferences sheet to the Preferences dialog box (Options → Preferences). This preferences sheet allows you to specify which fonts are to be used when rendering MathML.

Figure 4. The MathML preferences sheet

Notice that, by default, the standard Java™ logical fonts (Serif, SansSerif, Monospaced) are also used to render the MathML elements.

There are situations where you'll want to change the above mapping. For example, on the Mac, the Serif logical font is mapped to the Times physical font and this font is intrinsically too small. In such case, you may use the "Choose font from list" button found at the right of each font field. This button displays a list allowing you to choose any True Type font installed on your system.

Figure 5. Dialog box displayed by the "Choose font from list" button

Alternatively, you may use the "Choose font file" button found at the very right of each font field. This button displays the standard file chooser which allows you to specify any .ttf or .otf font file, whether this font has been installed or not on your system.

4.1. Bundled math fonts

The MathML add-on is bundled with the following math fonts:

Logical MathML Font	Bundled Font (found in mathml_addon_install_dir/fonts/)	Origin
normal	STIXTwoMath-Regular.otf	STIX Fonts
bold	STIXTwoText-Bold.otf
italic	STIXTwoText-Italic.otf
bold-italic	STIXTwoText-BoldItalic.otf
fraktur	typographerfraktur.medium.ttf	Free fonts from 1001 Fonts
bold-fraktur	typographerfraktur.bold.ttf
script	tangerine.regular.ttf
bold-script	tangerine.bold.ttf
double-struck	sortefax.medium.ttf

If you want to use the all above bundled fonts, simply click on the "Use bundled fonts" button. If you don't like the bundled fonts and want to restore the default settings, click on the Reset button.

	If you choose to use the bundled STIX Fonts, you may have to add attribute mathvariant="normal" to some mi elements. Example, the STIX fonts cannot render the infinity symbol U+221E in italic (the default for all mi elements), therefore you'll have to change <mi>&#x221E;</mi> to <mi mathvariant="normal">&#x221E;</mi>. Note that this is consistent with MathJax which uses the same STIX fonts.