I'm disappointed no browsers other than Firefox support it anymore.[0] Chrome dropped support in version 47.

It's very rare to see it used in the wild too, probably because it's not "sticky" across page loads.

0: https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/...

Me too. I do use it. It is very useful when you redesign a site and want to compare them. Just switch between themes and you instantly see if something is pixel-perfectly at the same spot.

I think it should be "sticky" the same way non-submitted form content stays persistent across page-reloads.

This kind of features should be what browsers are judged and compared on.