And me around 20 years - also never even heard of the `with` statement! I think to qualify as a footgun, people actually need to be using it in the real world.
I have seen it in the wild. I first learned of it from Douglas Crockford’s JavaScript the good parts. He also had some things to say about the new keyword and prototype inheritance and how we should stop using them. Ironically while he was dismissed on that suggestion then, VueJS has pretty much implemented exactly what he has in mind in their V3.