That's trickier, because currently a sample is generated only for the first supported language found in a font, we look for English first, and maths fonts are always going to contain Latin characters. For technical fonts it's probably best if the packager provides their own icon and screenshots, linked from the metainfo.xml. This probably makes it more straightforward to apply fancy TeX-style typesetting to maths fonts to show them at their best, too. -- Peter Oliver