How can I retrieve Heroku application id?

问题

I am being asked for heroku app id (the app123@heroku.com) by 3rd party support. I am quite sure there was some way to do get it, but I don't see it know. It's not featured in heroku info even in the more verbose --json mode.

How can I retrieve it?

来源：https://stackoverflow.com/questions/62796668/how-can-i-retrieve-heroku-application-id