Oooh, that's exactly the problem I had these days. The Firefox extension "Firefox translations" uses a tool (bergamot-translator) which requires SSE4 (or is it SSE3.1?) to run at all, so on all slightly old machines it fails miserably with a weird error. (90% of the machines I see around are 5 to 10 years old, work perfectly and don't need to be replaced, thank you very much, save money, think of the planet, this sort of things).