GUI.Button child stretching

Hi, I’m sorry to address you so often, but the point is the time limit) I can not figure it out. Why is the first child of the button (background) behaving normally and the other child (orange background of the button) stretched ??

All this is done in order to fix the arrangement of elements that breaks on mobile devices (different resolution), the buttons simply "run" against each other, I found a tip here on the forum that you need to set the sizes and positioning of the elements in percent, I will be glad to any comments on this )

When the buttonContainer is stretched, the golden background is stretched, but why is the background not stretched? unclear

backgroundActive.stretch = BABYLON.GUI.Image.STRETCH_UNIFORM;

Need to add this line, a lot of time is gone, well, maybe someone will come in handy)