This happened before I got into web development.
One day me and my best friend (already a developer) was try to download some pirated software on the internet. We found a website which allowed us to download the software but after completing a survey. We completed it but then we landed on another one and this guy sitting next to me took my laptop and deleted the survey pop-up doing something with the chrome developer tools. I was really freaked out and then he told me that is normal and left myself wondering.
Sorry about my bad English