title: Qt 5.9.5 in Ubuntu 18.04.1 LTS Error "GtkDialog mapped without a transient parent. This is discouraged"
body: <p>I've just installed Ubuntu 18.04.1 LTS and have just installed and am trying to run Qt but whenever I open a dialog box within Qt, such as when I want to Open an existing Project or File, it causes Qt Creator to freeze until I terminate it. Creating a new Project or File does not cause this to happen (different kind of window I imagine).</p>
  
  <p>The version I have is Qt Creator 4.5.2 based on Qt 5.9.5.</p>
  
  <p>I tried running <code>qtcreator</code> from the command line and when I go to open a file or folder from within the GUI the command line returns the following (and the GUI freezes):</p>
  
  <pre><code>    $ qtcreator
      Gtk-Message: 01:33:28.712: GtkDialog mapped without a transient parent. This is discouraged
  </code></pre>
  
  <p>Note, the Gtk-Message only occurs when I do something in Qt that would bring up a dialog box such as to navigate to and select a file. The Qt GIU freezes at this point.</p>
  
  <p>I hope someone knows how to fix this or if it's a compatibility issues between Ubuntu 18.04 and the versions of Qt Creator and Qt that I am using.</p>