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.
'a component returning text node between two text nodes',
        async render => {
          const B = () => 'b';
          const e = await render(
            <div>
              {'a'}
              <B />
              {'c'}
            </div>,
          );
          if (
            render === serverRender ||
            render === clientRenderOnServerString ||
            render === streamRender
          ) {
            
            expect(e.childNodes.length).toBe(5);
            expectTextNode(e.childNodes[0], 'a');
            expectTextNode(e.childNodes[2], 'b');
            expectTextNode(e.childNodes[4], 'c');
          } else {
            expect(e.childNodes.length).toBe(3);
            expectTextNode(e.childNodes[0], 'a');
            expectTextNode(e.childNodes[1], 'b');
            expectTextNode(e.childNodes[2], 'c');
          }
        },
      );
      itRenders('a tree with sibling host and text nodes', async render => {
        class X extends React.Component {