Effective from June 1, 2020
We have added a new parameter api_domain to OAuth /oauth/token responses.
For now, only the apps created on or after February 20, 2020 will see the new parameter in the OAuth /oauth/token response.
On June 1, 2020, the code will automatically start sending the new parameter to all requests i.e. apps created before February 20, 2020 will also start seeing the new parameter in the OAuth /oauth/token response.
Continue reading about the change here!