https://adnauseam.io/ There you go. Not on the chrome extensions store, but works on chrome (according to their site, I can only vouch for Firefox). I had this question a while ago, and debated building my own, but laziness won out. Edit: I'm an idiot, didn't read that you specified random websites. Adnauseam just clicks on random ads to pollute marketing data.

Why are these people not creating spaceships, exploring the deep of the oceans, or curing cancer?

There is no advertising money in those fields.

Lest you think this is an exaggeration, graduate students and postdocs make peanuts, who would be doing the cancer research, make peanuts.

Starting salary for a postdoc is a bit less than $50k, and this is after 5+ years of grad school, during which you make even less (often $20-30k) One can expect to be a postdoc for 3-5+ years before becoming remotely competitive for an independent (faculty) position, and another 5 years before the job is relatively secure. The competition for these jobs—and the remaining industrial ones—is savage and unpredictable.

This is bad for so many reasons: frantic people don’t do careful experiments or do good science, very smart people opt out all together and figure out how to make you click on ads instead, and a lot of time, money, and effort gets wasted in the churn.

If you want more cancer research and less ad optimization, nag your reps to improve how we fund research!

I feel like you could pull a 'natural flow' subset out.

I feel like searching for natural flow will not give me the results I want.

Not if you have a natural flow for all the random visits.

I mean, at that point you're having an arms race against Facebook's machine learning. My money's on them.