MouseArea containsMouse is incorrect while button is pressed on another MouseArea

The value of 'containsMouse' is not correct when mouse button is held when the cursor enters the mouse area. To replicate with the attached sample app:
1. Left click in the outer mouse area (white), then
2. Drag the cursor into the center rectangle.

I would expect that after step 2 the rectangle should change color. Even after releasing the mouse button inside the mouse area, the rectangle does not change color until the mouse moves inside the area without a button being pressed.