Create prototype Chrome Extension capable of inserting HTML into a Draft.js/React editor and correctly updating state

We have an existing Chrome Extension that is able to insert HTML/text from a library of snippets into just about any editable element on a webpage. The Extension is for teachers - so they can create and share libraries of comments, then quickly use them to comment on Google Docs and similar. A new platform we want to work with has a text entry area that is built in React and uses, we believe, Draft.js. Our existing code can insert text into the Dom but of course the state of the editor isn't updated and mayhem ensues. We'd like some basic proof of concept research and a quick prototype to prove that a string, from a Chrome Extension, can be inserted as HTML into the editor and correctly trigger/update the editor. I have attached some documentation on the editor in question - the HTML visible for the editor and the [login to view URL] that must house the JS that runs it... Our code / app isn't relevant - the goal is to prove that a string (which could be a variable in a content or background script - hardcoded) can be placed into the editor with the equivalent effect to typing it yourself. Options may include injecting a script into the page via a content script.