I clicked on some stupid link on Facebook earlier that then posted something on my behalf to facebook without me wanting it to. Since then seems to be a bit fishy - I was logged out of here, and just noticing odd font things like the autofill that shows up in here is all suddenly bold and never has been, and when I go to Google the font on there is much bigger than usual.

I'm on a mac and use Chrome. Can I check if something spooky is going on like a virus?