Draft-js: JS .blur() on Draft editor causes in-progress composition to be lost

[altano]

Do you want to request a feature or report a bug?
This is a bug.

What is the current behavior?
When in composition mode (e.g. using a US - International or Korean keyboard) in a Draft editor, pressing tab moves focus out of the editor AFTER committing the in-progress composition. It looks like this:
✅✅✅✅

If the Draft editor loses focus for other reasons (e.g. JS calls .blur() on the editor element) the composition is erased instead of being committed. It looks like this:
❌❌❌❌

In this gif I am calling:

  setTimeout(() => {
    console.log("Blurring NOW", document.activeElement);
    document.activeElement.blur();
    console.log("Active element is now: ", document.activeElement);
  }, 5000);

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem. You can use this jsfiddle to get started: https://jsfiddle.net/stopachka/m6z0xn4r/.
Reproduces in Chrome+macOS.
Does NOT reproduce in Firefox+macOS.

1. On macOS, add "2-Set Korean" to your keyboards and switch to it
2. Open this codesandbox
3. Type into the input something that enters composition mode, e.g. "gksrmf"
4. Wait a few seconds for the JS to call .blur() on the Draft editor
5. The in-progress composition will be deleted (just as in the gif above)

What is the expected behavior?
The in-progress composition should remain (as it does in Firefox or when pressing tab).

Which versions of Draft.js, and which browser / OS are affected by this issue? Did this work in previous versions of Draft.js?
macOS Mojave (10.14.2)
Chrome Version 71.0.3578.98 (Official Build) (64-bit)
React 16.8.0
Immutable 4.0.0-rc.12
Draft.js 0.10.5

[goodhyun]

1632

1274

This is such an outstanding issue. too bad we didn't find a solution up until now.

[claudiopro]

Thanks for reporting this issue @altano!