title: Xcode 10.1 opening wrong file
body: <p>Just downloaded Xcode 10.1. I have Preferences->Navigation->Double Click Navigation set to 'Uses Seperate Window' as I usually do. However double clicking any file in the project opens a window but the contents of that window is the wrong file. Whichever file I double click on, the same incorrect file opens. If I change double clicking to open in a tab, the correct file is opened...</p>
  
  <p>The problem appears to be just one project. </p>
  
  <p>Have tried a 'Clean Build Folder' to no avail</p>
  
  <p>It was working fine in 10.0</p>
  
  <p>I open the project using the xxxx.xcworkspace (as I have pods in the project).</p>
  
  <p>If I open a new window and view a specific file there then go back to my window with the list of files and double click that file, the correct window is brought to the front with the correct file visible.</p>