Demo breaks after specific combinations of nesting/unnesting operations

[e1himself]

I've managed to break the Demo editor mentioned in #7.

I've only used Tab or Shift-Tab on my keyboard to nest/unnest specific portions of text.

https://user-images.githubusercontent.com/370680/108207202-17681c80-7130-11eb-9a56-698b42723b35.mp4

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Browser: Firefox 85.0.1 (64-bit) for Ubuntu

[kamilmielnik]

Thanks for the report!

I believe I've fixed it - I cannot reproduce it anymore.

@e1himself can you please give it a try? :pray:

https://codesandbox.io/s/prezlyslate-lists-demo-complete-example-h9xxi?file=/src/App.tsx

[e1himself]

Thanks @kamilmielnik!

It seems to be fixed now.

Good job! :+1: