title: IntelliJ sees multiple ghost modules in the project
body: <p>I have only one module in the project, named <code>FilterWidget</code>. Despite that, <code>IntelliJ</code> sees multiple "ghost" copies of it:</p>
  
  <p><a href="https://i.stack.imgur.com/SvZII.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SvZII.jpg" alt="enter image description here"></a></p>
  
  <p>All these modules allow partially separate, partially shared setup, which creates a mess.</p>
  
  <p>What is it and how to fix?</p>