Andre, we need to severely trim quotes when posting by email. A summary with added info.

Andre: 2000 pixels / 183 mm = 10.9 pixels / mm
Terry: 1440 pixels / 336 mm = 4.3 pixels / mm
Andre: Windows Display setting text size, custom scaling = 200%, 200%
Terry: "                                               " = 125%, none
Andre: 8 mm tall taskbar needs zoom 'margin' of 178.
Terry: 11 mm tall taskbar needs zoom 'margin' of 114.

I don't see now to get from px/mm, settings, and bar height to the needed zoom correction.

Conclusion 1: The previous Windows zoom margin of 78 is likely better for people with stock Windows (text size = 100%), making the change to 114 in PR 13575 wrong for them.
Conclusion 2: No value is right for all Windows users.  I assume this is also true for Linux and Windows.

Conclusion 3: We need to somehow calculate a specific correction from information available from tkinter.  If necessary, add a 'Configurtion' button to the Options menu or Settings dialog.  Display a maximized text window, have user verify that it fits properly, and get geometry.