Wish I knew the answer. Seems to come in cycles. At one point I had to stop using the browser version of Android Central forums. Can't discern a pattern. Seems to move from one browser site to another periodically.
I've always been suspicious of Verizon but I have nothing to back that up.
I'm just as interested in an answer as you. Been a couple of weeks since I encountered this particular evil. As I said, they seem to move around.