Well I spent most of the morning yesterday trying to figure out why all of a sudden my Admin bar was all messed up in Google Chrome (45). The back-end looked fine in all other browsers. Digging thru a few threads, I found the simple answer and fix. Here it is:
Type this in your Chrome address bar (it brings up settings)
Enable the Disable slimming paint flag. (should be 1st one)
Ensure that the Enable slimming paint flag below it is not turned on.
Full bug report here:
Hope this saves a few of you from pulling your hair out. I know I don't have much left.
Have a great weekend.