**Do you want to request a *feature* or report a *bug*?**
Bug

**What is the current behavior?**

React 16.10.0 has broken all Next.js applications (and potentially other SSR solutions).

It appears you cannot `hydrate` in conjunction with a client-side `<Suspense>` component.

> Expected to have a hydrated suspense instance. This error is likely caused by a bug in React. Please file an issue.

![image](https://user-images.githubusercontent.com/616428/65810696-7f087b00-e17b-11e9-9957-3481fb5853e3.png)


**CodeSandbox**: https://codesandbox.io/s/i66g1

**What is the expected behavior?**

Not entirely sure -- I'm opening this issue to discuss. The provided example worked in React 16.9.0 (and prior releases containing Suspense).

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**

`react@16.10.0`/`react-dom@16.10.0` is broken.
`react@16.9.0`/`react-dom@16.9.0` works.

<a>Click me</a>
        </div>
      );
    }
    let finalHTML = ReactDOMServer.renderToString(<App />);
    let parentContainer = document.createElement('div');
    let childContainer = document.createElement('div');
    
    document.body.appendChild(parentContainer);
    
    
    let parentRoot = ReactDOM.unstable_createRoot(parentContainer);
    parentRoot.render(<Parent />);
    Scheduler.unstable_flushAll();
    childSlotRef.current.appendChild(childContainer);
    childContainer.innerHTML = finalHTML;
    let a = childContainer.getElementsByTagName('a')[0];
    
    let root = ReactDOM.unstable_createRoot(childContainer, {hydrate: true});
    root.render(<App />);
    
    a.click();
    expect(clicks).toBe(0);
    Scheduler.unstable_flushAll();
    
    expect(clicks).toBe(1);
    document.body.removeChild(parentContainer);
  });
});