I happen to use Zorin OS 15.3 lite edition although I purchased the ultimate edition to support this amazing Linux distribution recently.
There is an annoying issue that I’ve experienced with the XFCE desktop reference the rounded bottom corners of the windows. I’m using an Asus R420MA laptop that has a set resolution of 1366 x 768. With the rounded corners radius patch that Zorin OS uses it makes it very difficult to resize a window using either the lower left or right corners of the window because the grab area is much smaller. I resorted to using the following command to completely remove the rounded radius:
xfconf-query -c xfwm4 -p /general/rounded_corners_radius -s 0
Maybe this can be a setting that is implemented or the rounded corners patch could be completely removed. Just a friendly suggestion.
Thank you again for a great Linux distribution. I’m glad I found it.