Pupeteer like browser control over devtools protocol in basic Karma

test.ts

fetch('http://localhost:9222/json')
    .then(response => response.json())
    .then(([response]) => {
        const socket = new WebSocket(response.webSocketDebuggerUrl);

        socket.onopen = () => {
            socket.send(
                JSON.stringify({
                    id: 1,
                    method: 'Browser.grantPermissions',
                    params: {
                        origin: 'http://localhost:9876',
                        permissions: ['midi', 'midiSysex'],
                    },
                }),
            );
        };
    });