When starting the settings window actually appears for parts of a second and afterwards after being activated via the icon for the first time - it is located at the upper left corner whereas all other activations show it in the center of the screen.
The flashing seemed to be connected to the window being marked as "visible=true" in glade which was all wrong. We start with hidden window now and show it when needed. The displacement seems to be connected to this problem, it's gone on my computer now.
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The flashing seemed to be connected to the window being marked as "visible=true" in glade which was all wrong. We start with hidden window now and show it when needed. The displacement seems to be connected to this problem, it's gone on my computer now.