I also use Avast (and the paid version of Malwarebytes), but I do not get these warnings. Of course I have all the ads blocked. AdBlock is your friend ;). Especially useful since I'm sure Rendo does not check code on the ads it allows on the site and because of the rising tide of ransomeware in advertisements. You might also want to run Malwarebytes Anti-Exploit (there is a free version and I run that as well).

Laurie