I checked out USMB on my Fire tablet and saw it, also. I assumed all mobile devices had it, as I only log in from tower computer on my desk.
The problem seems to be confined to phones, never see it from my desktop at all.
Both of you are correct. Because he is zoomed in so far, this ad is probably from his phone carrier and does not overlay the USMB page formatting very well.
Grampa Murked U -- connect thru your home Wifi and see if it's still there. And get "computer glasses".. There is such a thing. That way you'll have more than 300 characters on your phone screen at the same time.. LOL....
I am officially old and set in my ways, given. I like USMB, but would rather be in hell with my back broke than to actually do USMB on my iphone or Fire tablet. Here I get full screen on a big screen and keep that screen set to 150%. I do not even have to use my no line trifocals, almost as if I was normal like I used to be. Sweet deal.
When I was actively moderating and still doing electronic product development, I worked from a dual display work station. Had to.. I'd have 2 windows open and a dozen tabs just for my USMB "breakroom"... Only recently, after buying a 10.5" IPad did I even TRY to use USMB on it.
Ironically, part of what did in research and for products was designing user interfaces. And most mobile devices violate nearly every damn ergodynamic rule that exists. Especially visual acuity at distances and touch zone sizing.