Backspace key not working on iOS Safari 10.x

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monaco-editor version: 0.9.0 (on the demo site as of 2017/07/27)
Browser: Safari
OS: iOS 10.3 (simulator)
Steps or JS usage snippet reproducing the issue:

1. Input any Japanese characters (i.e. "こんにちは")
2. Push the backspace key

The cursor goes back but the characters are not deleted.

Once the input is fixed, the backspace key works as expected.