src/Pure/PIDE/isar_document.ML

     (fn [versions_yxml] => Document.change_state (fn state =>
       let
         val versions =
           YXML.parse_body versions_yxml |>
             let open XML.Decode in list int end;
-      in Document.remove_versions versions state end));
+        val state1 = Document.remove_versions versions state;
+        val _ = Output.raw_message Markup.removed_versions versions_yxml;
+      in state1 end));
 
 val _ =
   Isabelle_Process.add_command "Isar_Document.invoke_scala"
     (fn [id, tag, res] => Invoke_Scala.fulfill_method id tag res);