This might be a reference to this one: https://github.com/facebook/react/issues/10212#issuecomment-346302374

The problem still exist.

So, trying to render with server side and got this error. I don't have this notation in my code but this might be a problem with dependencies.

```
TypeError: Cannot read property 'toLowerCase' of undefined
    at ReactDOMServerRenderer.renderDOM (/Users/lukasborawski/Dev/web-client/node_modules/react-dom/cjs/react-dom-server.node.development.js:2304:27)
...
```

```
"react": "^16.1.1",
"react-dom": "^16.2.0",
```

Thx for help.
type: mixed,
  domNamespace: string,
  children: FlatReactChildren,
  childIndex: number,
  context: Object,
  footer: string,
};
type FrameDev = Frame & {
  debugElementStack: Array<ReactElement>,
};
class ReactDOMServerRenderer {
  stack: Array<Frame>;
  exhausted: boolean;
  // TODO: type this more strictly:
  currentSelectValue: any;
  previousWasTextNode: boolean;
  makeStaticMarkup: boolean;
  providerStack: Array<?ReactProvider<any>>;
  providerIndex: number;
  constructor(children: mixed, makeStaticMarkup: boolean) {
    const flatChildren = flattenTopLevelChildren(children);
    const topFrame: Frame = {
      type: null,
      
      
      domNamespace: Namespaces.html,
      children: flatChildren,
      childIndex: 0,
      context: emptyObject,
      footer: '',