https://dejanseo.com.au/competitor-hack/

QuoteHere's what I did:

User lands on my page (referrer: google)
When they hit "back" button in Chrome, JS sends them to my copy of SERP
Click on any competitor takes them to my mirror of competitor's site (noindex)
Now I generate heatmaps, scrollmaps, records screen interactions and typing.

Sounds cool, though I assume they wouldn't be able to get the original referring keyword, so it must be difficult to compare like for like competitor URLs

I didn't think browsers allowed you to hijack the back button like that anymore. That's nuts. Brilliant on his part. Nuts on the browser maker's part.