app3.js

// frontend/src/App.js:45
if (chatClient && channel) {
    return (
        <div className="App">
            <Chat client={chatClient} theme={'messaging light'}>
                <Channel channel={channel}>
                    <Window>
                        <ChannelHeader />
                        <MessageList />
                        <MessageInput />
                    </Window>
                    <Thread />
                </Channel>
            </Chat>
        </div>
    )
} else {
  // ...
}