[cozuya]

If you're talking about actual new windows that are a separate process, those have been blocked by popup blockers for years. As far as popovers that block the screen/annoy you, those are just HTML elements that are positioned on top of normal content - its not a "special" thing backed into the DOM API. There's really no effective way to stop a page from being able to do that unless you disable javascript entirely.

[nitrogen]

There have been tricks that get popups through, possibly by exploiting browser bugs or opening the popup in one of the few on* handlers where browsers allow them.