This is really awesome-- At Nylas we&#x27;ve &#x2F;also&#x2F; been building one for the past year to use in our email composer inside N1 (<a href="https:&#x2F;&#x2F;githbub.com&#x2F;nylas&#x2F;n1" rel="nofollow">https:&#x2F;&#x2F;githbub.com&#x2F;nylas&#x2F;n1</a>), with the additional constraint that it needs to support extension by third party plugins.<p>Building a nice declarative editing interface around an inherently mutable structure with an imperative API like the DOM (which can mutate state from under you, like focus) is a real challenge. <i>Props</i> to the team at facebook for this.