If you look closely at the banner, you'll notice that "P" from the MLPFORUMS is cut off, which is also the case with Trixie's back left hoof. I guess standards for such a popular forum isn't as high as I thought.
That's strange. It works fine for me, and I've not heard of other complaints since the banner was put up. We might need to tweak the CSS a bit. Would you like to provide a screenshot?
On my end, I just tested it without problems on multiple browsers, including mobile, and with different window sizes. I think it would be a good idea to post this concern as a Q&A thread to see if anyone else is experiencing similar issues.