This usually means that the user mixed up our lowercase/uppercase naming convention; see https://github.com/facebook/react/pull/3429#issuecomment-85166440.

We could add a message like

> Warning: The tag <commentBox> is unrecognized in this browser. If you meant to render a React component, start its name with an uppercase letter.

We'd check this only once per tag and only in development mode.

lastProps,
      nextProps,
      transaction,
      isCustomComponentTag,
    );
    this._updateDOMChildren(lastProps, nextProps, transaction, context);
    switch (this._tag) {
      case 'input':
        
        
        
        ReactDOMInput.updateWrapper(this);
        break;
      case 'textarea':
        ReactDOMTextarea.updateWrapper(this);
        break;
      case 'select':
        
        
        transaction.getReactMountReady().enqueue(postUpdateSelectWrapper, this);
        break;
    }
  },
  /**
   * Reconciles the properties by detecting differences in property values and
   * updating the DOM as necessary. This function is probably the single most
   * critical path for performance optimization.
   *
   * TODO: Benchmark whether checking for changed values in memory actually
   *       improves performance (especially statically positioned elements).