https://i.imgur.com/iwymopx.png
Sometimes it's in a new top bar on the page but cannot remember if that's only on Gmail.
Damn, that is some duplicitous ad copy, especially in light of recent events.
Every time I see that pop up, I think “does it block pop ups like this?”
It looks like they also make other browsers pay for ads while they post their own ads for "Google's Official Browser" at no cost:
https://imgur.com/a/exzor1l