So, I noticed that the default font Firefox uses on Android when nothing is specified is a sans-serif font. But I would like to use serif.

I've already seen an answer to change the values of "font.name.sans-serif.x-unicode" and "font.name.sans-serif.x-western" in about:config (also "font.name.sans-serif.x-user-def", but that must have been removed, nothing shows up when I search it), but I haven't gotten it to work. I assume I'm not inputting the right value. What should I set as the value to get it to use a serif font? Or is there another way I should do this?