anchor.diff:  
       // Re-focuses after setting editing state.
       domElement.focus();
  +  }
  +
  +  /// Prevent default behavior for mouse down, up and move.
  +  ///
  +  /// When normal mouse events are not prevented, in desktop browsers, mouse
  +  /// selection conflicts with selection sent from the framework, which creates
  +  /// flickering during selection by mouse.
  +  void preventDefaultForMouseEvents() {
  +    _subscriptions.add(domElement.onMouseDown.listen((_) {
  +      _.preventDefault();
  +    }));
  +
  +    _subscriptions.add(domElement.onMouseUp.listen((_) {
  +      _.preventDefault();
  +    }));
  +
  +    _subscriptions.add(domElement.onMouseMove.listen((_) {
  +      _.preventDefault();
  +    }));
     }
   }
   
  
positive.code:         domElement.focus();
        }
      }));
    }
  }
  
  
negative.code:         domElement.focus();
        }
      }));
  
      preventDefaultForMouseEvents();
    }
  
    @override
  