QML - Random gray rectangular appear on screen

[AviRot100]

pic. 1pic. 2

Hi,
I'm using :
Qt ver - Qt 5.15 MinGW 32-bit
Compiler - MinGW 8.1.0 32-bit
Debugger - GNU gdb 8.1

When running the application with Display adapter Intel(R) Iris(R) Xe,
a random gray rectangular appears on the screen, and the background of some widgets is missing, as can notice in the pictures attached (pic.1 is the expected result).
Any ideas?
Tnx