Lena realized she had been unknowingly watched — and had been watching others — through this invisible digital eye.

Curious and a little unnerved, she searched online and found a forum post titled — a browser extension that let you see who visited your profile, even if they didn’t leave a like or comment. In 2010, this felt like magic. But the flip side was: others could see your visits too.

At first, Lena thought it was a coincidence. But it kept happening — with different people. Someone was tracking who viewed what, even though ok.ru didn’t have an official “guest view” feature back then.