I don't have a public link to the method they used, but I heard of this technique on the Web Audio Slack channel, which you can join here: https://web-audio.slack.com/. Basically, as I understood it, they found a way to wrap the Chrome runtime in a VST plugin and load it in a DAW. I guess the process can be optimised, but I'm no browser internals expert. The community is quite friendly, so if you're interested you could join it and ask, I'm sure they'll be happy to share with you.