title: xaml block horizontal and vertical window size adjustment, diagonal change only
body: <p>I don't want to let my users change the window size horizontal and vertical. The only way they should resize the window is diagonally.</p>
  
  <p>Is there a way to do this?</p>
  
  <p>Thanks in advance.</p>
  
  <p>EDIT 1: Content scaling, maintaining proportions?</p>