diff --git a/src/include/ktexteditor/document.h b/src/include/ktexteditor/document.h
--- a/src/include/ktexteditor/document.h
+++ b/src/include/ktexteditor/document.h
@@ -396,6 +396,8 @@
      * Error message if any problem occurred on last load.
      * @return error message what went wrong on loading
      */
+    // TODO KF6: Not needed anymore since we show load trouble as KTextEditor::Message.
+    //      Remove all code which set m_openingErrorMessage
     QString openingErrorMessage() const;
 
     /*