Display: File Manager overlays on next screen

[mjb10]

I recently reinstalled instantos and everything is running fine but...
I have two(2) screen monitors: One from my laptop and another aside on the right connected by VGA.
First screen resolution is: 1366x768
Second screen resolution is: 1680x1050

I usually use two(2) windows opening the file manager and integrate it in one desktop on my first screen, but the second window overlays on top of my second screen.
Also Instantwm doesn´t draw the coloured border like another applications when I use it the same way( 2 windows in one desktop ).
On the Image, the Red Line in the middle indicates the separation of the two screens.

Only happens with my file manager, other applications works just fine and draws the coloured border.
This never happened before in my previous installation.

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