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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

} else if (node.tag === HostPortal) {
        
        
        
      } else if (node.tag === SuspenseComponent) {
        const current = node.alternate;
        if (current !== null) {
          const oldState: SuspenseState = current.memoizedState;
          const newState: SuspenseState = node.memoizedState;
          const oldIsHidden = oldState !== null && oldState.didTimeout;
          const newIsHidden = newState !== null && newState.didTimeout;
          if (oldIsHidden !== newIsHidden) {
            
            
            
            const primaryChildParent = newIsHidden ? node.child : node;
            if (primaryChildParent !== null) {
              appendAllChildrenToContainer(
                containerChildSet,
                primaryChildParent,
                true,
                newIsHidden,
              );
            }
            
            break branches;
          }
        }
        if (node.child !== null) {