title: "Launch Configuration" Shows up Blank When Trying to Export Runnable Jar?
body: <p>I've gotten this to work in the past, but now whenever I choose <code>File &gt; Export... &gt; Runnable JAR File</code> and select the drop-down menu <code>"Launch Configuration"</code>, all I get is a blank bar.</p>
  
  <p>How can I get my main class to show up?</p>