Recently I had two different online testes where a good chunk of the questions were about Javascript generators - a feature that is very hard to see in the wild

Recently I had two different online testes where a good chunk of the questions were about Javascript generators - a feature that is very hard to see in the wild. Thankfully I'm already employed, but this was not the case I would lose a good amount of time studying this subject in depth (only to not use it later)