src/java.desktop/unix/classes/sun/awt/X11/XContentWindow.java

*** 1,7 ****
  /*
!  * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 137,146 ****
--- 137,152 ----
          }
      }
  
      @Override
      public void handleExposeEvent(XEvent xev) {
+         if(parentFrame.isTargetUndecorated() &&
+            XWM.getWMID() != XWM.UNITY_COMPIZ_WM &&
+                 width <= 0 && height <= 0) {
+             // WM didn't send initial ConfigureNotify, so set the bounds here
+             setContentBounds(parentFrame.getDimensions());
+         }
          if (width <= 0 || height <= 0) {
              return;
          }
          super.handleExposeEvent(xev);
      }