/* this issue is partially related to RT-19288 */
Run attached application and click "Init".
You see stage "stage0".
Click "None" there. It creates child window with none type of modality.
Appeared "stage1".
Click Win there.
WINDOW_MODAL child window was created and was called "Stage2".
In stage2 click "App".

Now using round button "close" in the corner close stages in the next order: stage0, stage1, stage2, stage3.

All the hierarchy of windows was created with parent-child relationship, but when you close windows, parent closing doesn't lead to child closing.