title: Today Widget view moves / constraints unstable
body: <p>My today widget uses nested stackviews to lay itself out. However, there is slight movement / unintentional resizing when the window is dragged and also when users interact with the view:</p>
  
  <p><a href="https://i.stack.imgur.com/QP1g7.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QP1g7.gif" alt="enter image description here"></a></p>
  
  <p>The stackview is simply pinned to all four sides of the super view:</p>
  
  <p><a href="https://i.stack.imgur.com/HBtK0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HBtK0.png" alt="enter image description here"></a></p>
  
  <p>I'm not sure if I'm missing something specific to Today Widgets, or possibly UIStackview that is causing this movement to occur.</p>