Bug report: digits don’t show for me. (Interesting æsthetic, actually, unmarked tiles.) Firefox, Sway/Linux, Settings → Fonts → Advanced → “Allow pages to choose their own fonts, instead of your selections above” disabled, and web fonts blocked altogether via uBlock Origin.
It is, actually. Firefox's PDF renderer on text meeting certain conditions is the only thing I've encountered breaking in a similar way (not rendering text), in almost five years of using this configuration.
I expect it to just render with my chosen fonts. That's what everything else does.
Unrelated: I really wish the browser setting of "Allow pages to choose their own fonts, instead of your selections above" can be a per-origin setting. There are a small number of websites that use web fonts tastefully but for the majority I would prefer my own fonts.
