I would have liked to demonstrate this in the Text Edit example, but printing there does not work at all, see QTBUG-59689.

1. Start Qt Creator.
2. Go to "Tools" -> "Options..." -> "Text Editor" -> "Font & Colors".
3. In the "Family" combo box, select "Courier".
4. Click "OK".
5. Go to "File" -> "New File or Project..." -> "General" -> "Scratch Buffer" und click "Choose".
   An editor opens up.
6. Put some text into that editor.
7. Select "File" -> "Print..." from the menu.
8. In the native print dialog, click "Print" (or whatever that might show you).
   The printout is too small to read it. I attached PDFs created using "Microsoft Print to PDF". The prints on paper look the same.

Text on printouts should have a reasonable size. With Qt 5.7.1, this used to work correctly.