src/java.desktop/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java

@@ -857,11 +857,11 @@
     }
 
     @Override
     public void updateFocusableWindowState() {
         final boolean isFocusable = isNativelyFocusableWindow();
-        setStyleBits(SHOULD_BECOME_KEY | SHOULD_BECOME_MAIN | RESIZABLE, isFocusable); // set bits at once
+        setStyleBits(SHOULD_BECOME_KEY | SHOULD_BECOME_MAIN | ((!isFocusable) ? RESIZABLE: 0), isFocusable);
     }
 
     @Override
     public void setAlwaysOnTop(boolean isAlwaysOnTop) {
         setStyleBits(ALWAYS_ON_TOP, isAlwaysOnTop);