title: Why does utop flash?
body: <p><a href="https://i.stack.imgur.com/IaN3e.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IaN3e.png" alt="flash on"></a></p>
  
  <p>In utop (on osx), the black border around the yellow welcome message, and the red line between each command flash.</p>
  
  <p>I thought it might be telling me to update something, but I can't find any message.</p>
  
  <p>Is there a way to turn this off?  Or is it trying to tell me something?</p>
  
  <p><a href="https://i.stack.imgur.com/dwV0Z.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dwV0Z.png" alt="flash off"></a></p>