Window does not expand on Mac

Following tutorial, on the section about 3d mapping, and Solid Color on page 49 the color dialog does not expand enough to show the complete opacity slider. I've tried to expand the window and it does not react as a normal Mac OS window. It will expand left and right, but not up and down.
See screen shot. Thanks.

I've had this report once before: it's due to the second title bar that you see at the top of the dialog. However I can't reproduce it myself, unfortunately. Which exact macOS version are you using?

10.12.6 Sierra
thanks

I've had one report of this problem before and that was fixed by resetting the preferences for UF. To do this, make sure Ultra Fractal is not running, open a Terminal window and type the following:

defaults delete com.ultrafractal.UltraFractal.5

Then restart Ultra Fractal. You will need to enter your license key again, along with any other customizations that you may have made (but you won't lose any documents).

Thank you, work as described.