Megalodon object fails to instantiate in React builds

[alicerunsonfedora]

Originally noted from hyperspacedev/hyperspace-classic#1:

Note: this might be more related to Hyperspace itself than to all React apps.

Megalodon objects instantiate and function normally in a React app when running react-scripts start. However, when running react-scripts test or react-scripts build and then serving the built content, the instantiation fails.

In Hyperspace, the following error occurs:

TypeError: "n is undefined"
	t App.js:26
Ii16React	448 index.js:7
	f (index):1
	184 main.b0bd95cd.chunk.js:1
	f (index):1
	a (index):1
	e (index):1
	<anonymous> main.b0bd95cd.chunk.js:1
 react-dom.production.min.js:3869
ya16React	448 index.js:7
	f (index):1
	184 main.b0bd95cd.chunk.js:1
	f (index):1
	a (index):1
	e (index):1
	<anonymous> main.b0bd95cd.chunk.js:1

Steps to reproduce

1. In the App component, create a constructor and field for the client:

class App extends Component {
    client;
    constructor(props) {
        super(props);
        this.client = new Mastodon(accesstoken, baseurl + '/api/v1');
    }
}

2. Use that client for a task (say, passing it down to a ComposeWindow element):

<App>
    <ComposeWindow client={this.client}/>
</App>