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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

let React;
let ReactFeatureFlags;
let Fragment;
let ReactNoop;
let ReactCache;
let Suspense;
let StrictMode;
let ConcurrentMode;
let TextResource;
let textResourceShouldFail;
describe('ReactSuspenseWithNoopRenderer', () => {
  beforeEach(() => {
    jest.resetModules();
    ReactFeatureFlags = require('shared/ReactFeatureFlags');
    ReactFeatureFlags.debugRenderPhaseSideEffectsForStrictMode = false;
    ReactFeatureFlags.replayFailedUnitOfWorkWithInvokeGuardedCallback = false;
    React = require('react');
    Fragment = React.Fragment;
    ReactNoop = require('react-noop-renderer');
    ReactCache = require('react-cache');
    Suspense = React.Suspense;
    StrictMode = React.StrictMode;
    ConcurrentMode = React.unstable_ConcurrentMode;
    TextResource = ReactCache.unstable_createResource(([text, ms = 0]) => {
      return new Promise((resolve, reject) =>
        setTimeout(() => {
          if (textResourceShouldFail) {
            ReactNoop.yield(`Promise rejected [${text}]`);
            reject(new Error('Failed to load: ' + text));