The attached code responds to window resize by setting new min size for the window. It behaves just as expected on Windows, however on Mac it results in weird movements of window content, rendering garbage of window decorations, etc.

Although the testcase doesn't look nice it actually represents real world situation happened to CustomColorDialog of ColorPicker control when its window min size depends on the current window size.

On Windows everything works without any problem. Window size changes but content always correctly follows the current window size and no garbage observed. Moreover, resizing in some limited area below min size doesn't cause any relayout which still happens when running on MacOS.