anchor.diff:                  'loading Gist ID $gistId.');
         }
       }
  +  }
  +
  +  void _resetCode() {
  +    setContextSources(lastInjectedSourceCode);
     }
   
     void setContextSources(Map<String, String> sources) {
  
positive.code:     userCodeEditor.readOnly = value;
      executeButton.disabled = value;
      formatButton.disabled = value;
      reloadGistButton.disabled = value || gistId.isEmpty;
      showHintButton?.disabled = value;
    }
  
  
negative.code: 
    MDCLinearProgress linearProgress;
    Dialog dialog;
    Map<String, String> lastInjectedSourceCode = <String, String>{};
  
    final DelayedTimer _debounceTimer = DelayedTimer(
      minDelay: Duration(milliseconds: 1000),
  