JS Print Setup Install
Open Mozilla FireFox. Must be on version 5.6 of Firefox
Search the web for "JS Print Setup Firefox" or click this link:
Click the "Add to Firefox" button.
to downgrade to the 5.6 version follow this link https://www.wikihow.com/Downgrade-Firefox
Zebra GC420d Setup
Plug in Zebra printer.
Open Control Panels (right click Start menu) > Hardware and Sound > Devices and Printers.
The printer should show as the Designer GC420d
Right-click on printer and select Printer Properties.
Click on Printer Settings tab. Scroll to bottom and select “Override Application Default Settings“
Select "Always use drivers settings."
Click on “Advanced.”
Click “Printing Defaults”
Set “Darkness” to 15.
Set Width to 4.00 and height to 3.00
Click "Okay" to dismiss dialog box.
Click "Okay" to dismiss Properties window.
Right-click on printer icon and select “Printing Preferences."
Confirm that darkness is set to 15, width to 4.00 and height to 3.00.
Click on Labels button. A new page will open and the labels with print incorrectly.
With the page open showing the labels type Control + P to bring up the printer dialog box.
In Firefox settings click on “print”.
A print preview window will open.
Click on “Page Setup”.
Click on "Margins & Headers/Footers".
Set all drop-downs in Headers & Footers to “Blank