Warning: I just updated my GIPHY extension this morning, as I sometimes need those funky animated GIFs, and when I clicked on a link in Reddit, I got an alertbox (Reddit says: Your computer has been infected by a virus, scan now?") and forwarded me to chromeupdates.top, which is clearly a malware site pretending to be Google.
I removed GIPHY and it's no longer popping up.
Disable GIPHY until this has been resolved.