I have a GUI app in built in custom tkinter, that uses a FigureCanvasTkAgg instance to embed a matplotlib figure. I also use a NavigationToolbar2Tk instance..well for navigation.

I all works fine, but I had an issue that if I ran the app on a screen with high DPI, then the buttons on the navigation bar became small relative to the other widgets, as well as the axes of the matplotlib figure.

I tried to figure it out, and searched online, but nothing seemed to work.
In many realated topics I saw this as a suggestion:

import ctypes
ctypes.windll.shcore.SetProcessDpiAwareness(2)

I tried it and everything turned enlarged and weird. I do not fully understand how this works, as I couldn’t locate the relevant documentation.

But when I changed it:

ctypes.windll.shcore.SetProcessDpiAwareness(1)

now it works perfectly… Intuitively I would think because the window now takes into consideration the DPI when showing the widgets, but I do not understand why this works.