src/Tools/jEdit/src/document_view.scala

     override def removeNotify() {
       ToolTipManager.sharedInstance.unregisterComponent(this)
       super.removeNotify
     }
 
+    val delay_repaint =
+      Swing_Thread.delay_first(Isabelle.session.update_delay) { repaint() }
+
     override def paintComponent(gfx: Graphics)
     {
       super.paintComponent(gfx)
       Swing_Thread.assert()
 

             val visible = visible_range()
 
             if (updated ||
                 (changed.nodes.contains(model.name) &&
                  changed.commands.exists(snapshot.node.commands.contains)))
-              overview.repaint()
+              overview.delay_repaint()
 
             if (updated) invalidate_range(visible)
             else {
               val visible_cmds =
                 snapshot.node.command_range(snapshot.revert(visible)).map(_._1)