--- old/src/java.desktop/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java	2018-06-25 11:03:54.000000000 +0100
+++ new/src/java.desktop/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java	2018-06-25 11:03:54.000000000 +0100
@@ -858,7 +858,7 @@
 
     @Override
     public void updateFocusableWindowState() {
-        final boolean isFocusable = isNativelyFocusableWindow();
+        final boolean isFocusable = isNativelyFocusableWindow() || (getOwnerFrameOrDialog(target) instanceof CEmbeddedFrame);
         setStyleBits(SHOULD_BECOME_KEY | SHOULD_BECOME_MAIN | RESIZABLE, isFocusable); // set bits at once
     }
 
@@ -1276,6 +1276,14 @@
         }
     }
 
+    private Window getOwnerFrameOrDialog(Window window) {
+        Window owner = window.getOwner();
+        while(owner != null && !(owner instanceof Frame || owner instanceof Dialog)) {
+            owner = owner.getOwner();
+        }
+        return owner;
+    }
+
     // ----------------------------------------------------------------------
     //                          NATIVE CALLBACKS
     // ----------------------------------------------------------------------