CRX screen will not stop climbing up

+1, I have seen this few times as well.

As stated by Scott, Change the Browser or try increasing/Decreasing the size. 

Just a guess, try ".stop()" of Jquery Link:- https://api.jquery.com/stop/ (Stop the currently-running animation on the matched elements.)

~kautuk

So many thanks. I solved the problem using Cntrl and resizing.