The best advice I am getting from ad ops and Google is close the browser, clean out your history and reopen the browser.
I have been assured that Google is working on finding the offending party.
For me, it's one ad in particular. There's an XFinity ad (which for me appears in Spanish for some unknown reason) that's mostly white space with a black border that says "scroll to continue." It blocks a very large portion of the screen and prevents posting for several seconds.
It only appears when I'm in the Forums. I don't even recall seeing it in the WBB forum, just the Husker Football forum.
I've already cleaned out my cookies and everything else in Chrome. I'll try seeing whether this ad appears if I'm using Edge and Firefox and let you know.
I don't mind the ads on the bottom of the screen because they all have an "X" allowing users to close them. The XFinity ad doesn't.