Spurious "Output doesn't fit on media" warnings

This has been a regular issue for me over the years, but now it seems to happen 100% of the time.

I create an image that is easily contained within the printable area of my printer, but when I go to print, it always has a "one issue" warning, saying the output doesn't fit on the media.

As an extreme example, I can create a new A4-sized image and draw a single 1cm square right in the centre of the page, and when I go to print on A4 paper, it STILL says it wont fit.

Every setting I can find is set to A4 and normal scaling, but to elaborate here is everything I can see....

My "New Image" size is set to A4

In the "Print" dialogue window's  "General" tab, the "Page" setting is set to "Match document (portrait)" and the "Print Style" is set to "Corel PHOTO-PAINT Defaults".

In the "Print" dialogue window's "Layout" tab, the  "Image position and size"  is set to "As in document"

Back on the "General" tab, opening the printer's "Preferences" box, gives me a new window for the printer itself and on that window's "Quick Set-up" tab I have the printer set to "Standard" settings and "Printer Paper size" is set to A4. Media type is "Plain Paper" and "Borderless Printing" is turned off.

In it's "Page Setup" tab, "Page Size" is set to A4 and "Page Layout" is set to "Normal Size".

My printer itself is set to A4 and the paper loaded is A4. The printer is a simple Canon MG5700 inkjet.

What more can I do to make this spurious (and incorrect!) warning go away? There is an option to "Not check for this issue again", but I would prefer it to just work properly!!!

Any advice would be gratefully received, thank you.