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.

(updatePayload = updatePayload || []).push(STYLE, styleUpdates);
    }
    return updatePayload;
  },
  
  updateProperties(
    domElement: Element,
    updatePayload: Array<any>,
    tag: string,
    lastRawProps: Object,
    nextRawProps: Object,
  ): void {
    var wasCustomComponentTag = isCustomComponent(tag, lastRawProps);
    var isCustomComponentTag = isCustomComponent(tag, nextRawProps);
    
    updateDOMProperties(
      domElement,
      updatePayload,
      wasCustomComponentTag,
      isCustomComponentTag,
    );
    
    
    switch (tag) {
      case 'input':
        
        
        
        ReactDOMFiberInput.updateWrapper(domElement, nextRawProps);
        break;