@Sean, I suspect that my ad-blocker, Ublock Origin, is preventing your posting with the sample ad from appearing. It blocked the whole posting, and not just the ad.
So I suggest testing your solution with Ublock Origin.
Like albada, Ublock Origin with mac firefox blocks the entire thread even though there is no advertising in it, since the included image is a png file.
I thought it was the poll, but I can see other threads with poll.
No problems in safari with magic lasso as a blocker (it allows you to see advertisers' posts, the rest blocks it), I don't have any problems with DuckDuckGo on mac either