Smart phones are not immune to adware, spyware, and the such. Most of my PC clean ups is from ad junk from this site. Just saying.

Reported guys, I'll try to block.

It has only happened to me when viewing the full site and never with the mobile skin.

Should not have said that. LOL.
It happened to me with the mobile skin tonight.

Solution that got rid of it was shut phone down and then do all the updates on my apps. It went away after that.

Happens to me frequently on both older and newer Android/ Google phones. It never seems to happen anywhere but this site and I believe it started when the site was updated or improved or whatever they choose to call it.