I keep getting an ad that shows up BELOW my notification bar. It is NOT in the notifications, nor on the homescreen, as far as I can tell.
I am using CyanogenMod 12.1 nightlies on a HTC M8. Screenshots below.
How can I get rid of this thing? It just showed up one day. I don't remember installing anything new (although I have autoupdate on for apps, and some update very often) right before it started. I tried ad scanners, but they haven't been much help.
I would rather not factory reset.
I can close the ad by clicking the small "x". If I click on the info button in the lower left corner, I can give feedback on the specific ad and ask not to see it again. If I click on opt out, it asks for my IMEI, which I'm not really comfortable providing.
The ads are all in Hungarian and Romanian. I live in Romania, close to the Hungarian border, so I'm guessing that is why.
(Click image to enlarge)
Opt out page: