[ncmncm]

Same. I particularly like Linux Libertine, enough so that I make Firefox use it everywhere, even (especially?) where the page designer wanted sans.

Sadly, mobile Firefox does not support that, so HN on Android is relentlessly sans.

[chrismorgan]

Even if the UI is not exposed, it’s all there in about:config and should work:

browser.display.use_document_fonts = 0

font.name.serif.x-western = Linux Libertine

font.name.sans-serif.x-western = Linux Libertine

[ncmncm]

Thank you, I had already done that. (Well, "Droid Serif".) For some reason it has no visible effect.

I never got the "Linux Libertine O" fonts to work in my phone. I suspect it doesn't like the file format.