It is proven! I am schroeder on Keybase: https://keybase.io/schroeder/sigchain#6fc90de77ca44a16f8fa3ac49ef56106f4855cca5c2bc32b7bedd1b8c697e1340f
Change your Twitch password, enable 2FA, and change your stream key. Right now. Do not wait.
You'll also need to reauthenticate with any third parties like Sery_Bot, StreamElements, Streamlabs, etc.
!reauth in Sery_Bot's chat or the link in thread.