View port doesn't scale - Control Cube hidden

in New Users
When I have a scene loaded, I like to see it fairly large sometimes. So, I minimize the tabs to make the view port large. Other times, I need to see tab groups; scene tab, content library, paramaters tab, etc. When I open the tab groups, the control cube is no longer visible. It's behind the tab groups. (see screen capture - top)
Any idea why this happens? I also noticed that the view port doesn't scale down all the way when I open tabs groups. (see screen capture - right side compared to left side)
Did I bump something? Can it be fixed?
Thanx!


Capture.JPG
1919 x 1017 - 180K
Comments
Close the Shader Builder and Shader Mixer panes that are docked with the Viewport.
That fixed it. Thanx.