How to prevent ad popups shown always on top?

[niutech]

The Document PiP could become a "wet dream" for all kinds of aggressive advertisers, which could serve always-on-top intrusive ad popups disturbing users while browsing web pages. How will you prevent such an unpleasant behavior?

[drmercer]

For whatever it's worth, this is also a problem for regular browser pop-ups, and browsers have pretty effectively solved that problem by requiring user interaction to open a popup. If that's a requirement for Doc PIP too, then I doubt this will be a problem here

[AffluentOwl]

I'd like my popups to be able to make their own popups. Here's a proof of concept: https://youtu.be/GF5bR6GE2rk?t=15 (Part 2)

[yisibl]

Suggested adding a button that would un-top it.