The page says "I deleted Chrome, and all the files Keystone had littered on the computer, restarted, and it was so snappy it felt like a brand new computer. Yeah, I realize this sounds like a freakin' infomercial, but it worked so well I spent $5 on a domain name and set up this website even if it makes me sound like a raving nut."

To then "wonder what the motivation is" is to suggest that you don't believe this simple positive explanation, and imply there's something less simple, and more scheming.

Yeah, there was no super master plan here, just that after dealing with one sluggish computer for days (you name it, I tried it), and another one for 5 years... the fact that it turned out to be slow because of an app that wasn't even running was pretty frustrating.

Filing a bug report that would get "works on my machine"'d and then ignored and auto-closed by a bot in 5 years didn't quite feel worthy.

Auto-updating browsers are a good idea. Keystone is bad auto-updating software. It should probably get scrapped.

What's a good way to verify that I've removed Keystone completely? Google doesn't provide any sort of uninstaller or uninstall instructions.

try `mdfind keystone` in terminal