Could we get the URL to check if any 3rd party HTML is injecting into the page?
What do your HTML includes look like?
Have you cleared your browser cache after your upgrade? (Control + F5)
Have you cleared the cache at any CDN that may be configured on the system after your upgrade? Cached resources can do all sorts of crazy stuff.
What browser are you using? Have you tested on other browsers? Other computers?
In our test forums here, do you experience the same display? (complete long shot)