Thank you for your patience. We have released custom domains for Azure AD B2C to public preview.
Documentation can be found here: https://docs.microsoft.com/en-us/azure/active-directory-b2c/custom-domain?pivots=b2c-custom-policy
An error occurred while saving the commentChuck Whitson commented
What is the current status of this?
This remains on our long-term backlog as something we want to offer