Haven't noticed any unusual pop-ups lately but I am using a couple of different browsers and they may have helped with this problem. I've been using Opera for about a month and just started trying Slim Jet. I kept having problems with all the Firefox browsers ( including Waterfox and Cyberfox ) so I got rid of all of them. IE-11 works fairly well as does Chrome. I just like to try something different sometimes.
You might want to give Opera a try.