Web Audio API Memory Leak

How should a web-audio-api AudioNode be cleaned up so that its memory is released? I am calling oscillatorNode.stop() and oscillatorNode.disconnect() based on this post, but it doesn't seem to help, and I end up with memory leaks. This post doesn't apply because I'm removing the references as soon as I stop the oscillatorNode.

I created a sample website that shows the issue. Here are the steps to reproduce.

1. Create a local html file and run the below code snippet in chrome on a desktop or laptop with dev tools open.
2. Create a heap snapshot.
3. Click the "Go" button.
4. Periodically create another heap snapshot.
5. Notice that the memory keeps rising, even after running the garbage collector. Why?

<html>
<body>
    <button onclick="go()">Go</button>
    <button onclick="cancel=true">Cancel</button>
    <div id="status"></div>

    <script>
        var cancel = false;
        var statusEl = document.getElementById('status');

        async function go() {
            cancel = false;
            for (var i = 0; i < 100000; i++) {
                if (cancel) {
                    return;
                }
                statusEl.innerHTML = i;
                play();
                await new Promise((resolve) => { setTimeout(resolve, 1); });
                stop();
            }
        }

        var ctx = new AudioContext();
        var data = {
            oscillatorNode: null
        };

        function play() {
            if (!data.oscillatorNode) {
                // create an oscillator
                data.oscillatorNode = ctx.createOscillator();
                data.oscillatorNode.frequency.value = 220.0;
                data.oscillatorNode.connect(ctx.destination);
                data.oscillatorNode.start(ctx.currentTime);
            }
        }

        function stop() {
            if (data.oscillatorNode) {
                data.oscillatorNode.stop();
                data.oscillatorNode.disconnect();
                delete data.oscillatorNode;
            }
        } 
    </script>
</body>

</html>