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**Do you want to request a *feature* or report a *bug*?**
bug, I believe, unless I misunderstand how it works
**What is the current behavior?**
Given a `Suspense` inside `Suspense` case like
```
<Suspense fallback="Fallback 1">
  <LazyText1 text="First text" />
  <Suspense fallback="Fallback 2">
    <LazyText2 text="Second text!" />
  </Suspense>
</Suspense>
```

Promises in `LazyTexts` start resolving at the same time, but if `LazyText2` is resolved first it never renders, `Fallback 2` stays.

Result:
```
First text

Fallback 2
```

Please see https://codesandbox.io/s/234o4zry7n

**What is the expected behavior?**

Every `LazyText` displayed in the end
```
First text

Second text!
```

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
react, react-dom 16.6.0

node.childExpirationTime = expirationTime;
        if (
          alternate !== null &&
          alternate.childExpirationTime < expirationTime
        ) {
          alternate.childExpirationTime = expirationTime;
        }
      } else if (
        alternate !== null &&
        alternate.childExpirationTime < expirationTime
      ) {
        alternate.childExpirationTime = expirationTime;
      }
      if (node.return === null && node.tag === HostRoot) {
        root = node.stateNode;
        break;
      }
      node = node.return;
    }
  }
  if (root === null) {
    if (__DEV__) {
      switch (fiber.tag) {
        case ClassComponent:
          warnAboutUpdateOnUnmounted(fiber, true);
          break;
        case FunctionComponent:
        case ForwardRef:
        case MemoComponent:
        case SimpleMemoComponent: