Printer-Friendly view - light grey boxes around form sections

CSS is the best option for tasks like this. See CSS examples here:
https://xlinesoft.com/phprunner/docs/customizing_styles_examples.htm

Also there are two videos that explain in depth the CSS topic:
https://www.youtube.com/watch?v=_DmMYRCUtU8
https://www.youtube.com/watch?v=yFnD38oslIc

Cool.

There are a couple of solutions....

1/ In the Print page Designer - you select each of the sections of the form and then under the Custom CSS (button on the right), simply insert;

:host {
border: none;
}

This sets the border for each individual section of the form.

Or 2/ as per the video tutorials, it's a case of finding the css Selector and Rule that applies to the grey lines around the form sections - and copy this into the Custom CSS section at the top of the Print page Editor. Then change the border to none; there. This applies the css style rule accross the whole Print page in one hit.