03 How to Automatic Print Using Mozilla Firefox (Browser)
FOR MOZILLA FIREFOX

1. Open Firefox and type about:config in the address bar and press enter.
2. Click to confirm that you will be careful.
3. Right click on the page, hover over New and click on Boolean.
4. Type print.always_print_silent as the preference name and click 'OK'.
5. Click on 'true' and click 'OK'.

After step 5, print dialog boxes will no longer pop up.