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.
return '';
      }
      if (this.makeStaticMarkup) {
        return escapeTextForBrowser(text);
      }
      if (this.previousWasTextNode) {
        return '<!-- -->' + escapeTextForBrowser(text);
      }
      this.previousWasTextNode = true;
      return escapeTextForBrowser(text);
    } else {
      let nextChild;
      ({child: nextChild, context} = resolve(child, context));
      if (nextChild === null || nextChild === false) {
        return '';
      } else if (!React.isValidElement(nextChild)) {
        if (nextChild != null && nextChild.$$typeof != null) {
          // Catch unexpected special types early.
          const $$typeof = nextChild.$$typeof;
          invariant(
            $$typeof !== REACT_PORTAL_TYPE,
            'Portals are not currently supported by the server renderer. ' +
              'Render them conditionally so that they only appear on the client render.',
          );
          
          invariant(
            false,
            'Unknown element-like object type: %s. This is likely a bug in React. ' +
              'Please file an issue.',
            ($$typeof: any).toString(),