Adjust Windowsize to Screensize/Maximize Window

[mikrocat]

Hi,

I want my Window to be Maximized when I open it. So i used

PlotWindow->showMaximized();

PlotWindow->showMaximized();

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The widgets height in my window does not fit in my screen so the windows display is cut off. If I double click on titlebar or minimize the window and maximize it again the window is shown completely.

I don't get what the difference between the doubleclick/MinimizeMaximize and the showMaximize function is. How can I set the correct size of the window/widget without minimize-maximize?