[kelnos]

> I've been doing front-end web dev for nearly ten years, and I've never even heard of those last two, much less used them.

Huh, that's interesting to hear you say that. I hardly do any web development at all, but I was using both of those things for personal/toy web sites over a decade ago.

Just goes to show you that even rank amateurs can end up exposed to things that professionals haven't seen, for whatever reason.