Opening this thread to keep track of the progress about the headless mode. I hope it will arrive in the near future.
I need it for my Insync Docker image: https://github.com/hadim/docker-insync/
The image works until it’s restarted, Insync fails linking an already existing account. Hopefully, v3 will fix this. See this issue for more details: https://github.com/hadim/docker-insync/issues/1