Help me understand ClientBounds - Offset in Android

Maybe someone here can help me understand, why the Window.ClientBounds is offset in Android:

This specific situation is as follows:

I have a Layout with 2 views, one on the top (which is for admob) and the gameview underneath it - I do NOT want to overlay the admob view, but have the gameview just shrink by that amound. The Ad will be loaded async so the view size eventually changes. Game is fullscreen, no bars visible. Landscape.

I have no problem reacting to this and recreate the backbuffer etc accordingly - anyway. The Device-Resolution is 1280x720 but after the “resize” the Window.ClientBounds is filled with (57,0,1166,656). But the ACTUAL size of the view is 1280x656 (because the width hasn’t changed at all in reality)… the width equals to 1166+572 … so I could basically fix it by using preferedwidth = bounds.width + bounds.x2 (but I don’t know if that will always work)

Does anyone know where this offset could come from - or what I can do to prevent it from happening?

edit: Just tried it on another (old) smartpone with different solution, and the width+x*2 seems to be valid there as well …

edit2: When removing that ad-view again (Visibility=Gone) - OnResize gets called but this the the bounds.y is offset. Here again, adding bounds.y*2 to the heigh fixes the bars problem. I “think” monogame tries to maintain the aspect ratio or something in the actual clientbounds