Zorin OS 16 Lite (XFCE) Theme Consistency

This is actually a duplicate tutorial, but the release of Zorin OS 16 Lite necessitates a more specific address.
Zorin OS 16 Lite (XFCE with XFWM4 Window Manager) is using XFCE 4.16 rather than 4.14.
XFCE 4.16 introduced XFCE native applications using CSD (Client Side Decorations) rather than the XFWM4 Window manager. Most applications still use the XFWM4 window borders, but some no longer do.
For a user that installs a custom or third party theme, this may not show their installed themes correctly.
There is a very simple way to correct this for your system: PCMans package gtk3-nocsd
Installing this forces the CSD applications to use the Window Managers borders, bringing consistency back to your themes on Zorin OS 16 Lite.

sudo apt install gtk3-nocsd && sudo reboot

That's it. Bear in mind that if you elevate to Root, you may still see CSD headers.

This Package does not work on GNOME (Zorin OS Core) and should not be installed on Gnome Desktops.