title: Why in Linux the order of modal windows changes when you click on the owner
body: <p>Good day. I am engaged in cross-platform development of desktop applications on JavaFX for Windows and Linux. The application is the main stage which is the owner for all subsequent open modal windows. When working in Window, when you click on the main stage, all windows lose focus and their order does not change, which I think is right.</p>
  <p>Windows open with focus on the last window (Windows OS)
  <a href="https://i.stack.imgur.com/TJla5.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/TJla5.png" alt="enter image description here" /></a></p>
  <p>Mouse click on the main stage, focus is lost, window order has not changed (Windows OS)
  <a href="https://i.stack.imgur.com/xdlp6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xdlp6.png" alt="enter image description here" /></a></p>
  <p>In the Linux operating system, when you click on the main stage, all modal windows lose focus and their order changes, which should not be.</p>
  <p>Windows open with focus on the last window (Linux OS)
  <a href="https://i.stack.imgur.com/yKhs4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yKhs4.png" alt="enter image description here" /></a></p>
  <p>Mouse click on the main stage, focus is lost, window order
  changed (Linux OS)
  <a href="https://i.stack.imgur.com/FdaPs.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FdaPs.png" alt="enter image description here" /></a></p>
  <p>Tell me what may be the reason for changing the order of modal windows in Linux with the loss of focus. All open modal windows have an owner main stage.</p>
  <p>Modal window settings when opening:</p>
  <pre><code>    setAlwaysOnTop(true);
      setResizable(false);
      setFullScreen(false);
      initOwner(owner);
  </code></pre>
  <p>OS Windows - 7</p>
  <p>OS Linux - Astra Linux Debian GNU/Linux CE 2.12.21 (Codename: Orel, Release: 2.12.21)</p>
  <p>The graphics subsystem on Linux operates using the <strong>Xorg</strong> graphics server.</p>
  <p><strong>Fly</strong> desktop, window manager <strong>fly-wm</strong></p>
  <p>Java 8, JavaFX 8</p>