title: Linebreak in R plot legend behavior
body: <p>I have a linebreak in a legend in R and my problem is that the graphic looks not as expected.
  My minimal example is as follows:</p>
  
  <pre><code>plot(1)
  legendLabel&lt;-c("t\nu ","tu","wh","trr\nni")
  legend("top",legend=legendLabel,horiz=TRUE,fill=c("red","blue","gray","black"))
  </code></pre>
  
  <p>I would expect that the upper and lower margin of the legend is equal, but this is not the case.<img src="https://i.stack.imgur.com/eS00I.png" alt="enter image description here"></p>
  
  <p>As you can see in the attached image, the lower margin is smaller then the upper.</p>
  
  <p>Does anybody have an idea how to fix it or can anyone tell me what the problem is?</p>
  
  <p>Thanks.</p>