src/Pure/System/system_dialog.scala

 
 import java.awt.{GraphicsEnvironment, Point, Font}
 import javax.swing.WindowConstants
 
 import scala.swing.{ScrollPane, Button, CheckBox, FlowPanel,
-  BorderPanel, Frame, TextArea, SwingApplication, Component, Label}
+  BorderPanel, Frame, TextArea, Component, Label}
 import scala.swing.event.ButtonClicked
 
 
 class System_Dialog extends Build.Progress
 {