Great... looks like the Chrome team is denying public access to this... and it wasn't captured beforehand in the wayback machine..
Gorhill's proof-of-concept extension code is still up: https://gist.github.com/gorhill/b0316e35d4e7e4a44df39e8b7fa5ac20. His tweets about it though have been deleted.
And now the Gist has been removed. But it’s available on Archive.is: https://archive.is/hi5o1