src/Tools/jEdit/src/active.scala

               case _ =>
                 if (props.contains(Markup.PADDING_LINE))
                   Isabelle.insert_line_padding(text_area, text)
                 else text_area.setSelectedText(text)
             }
-            text_area.requestFocus
+            text_area.requestFocus()
           }
           true
 
         case Protocol.Dialog(id, serial, result) =>
           model.session.dialog_result(id, serial, result)