OAuth 2.0 Resource Owner Password Credentials (ROPC), also known in Postman as the 'Password Credentials' OAuth 2.0 Grant Type.
See here for more information: https://docs.microsoft.com/en-us/azure/active-directory/develop/v2-oauth-ropc
The current allowed method from the Generic OAuth 2.0 - Generic Oauth 2 Identity Provider only allows for: Client id & Client secret.
This does not grant access to OAuth 2.0 APIs that use a 'Password Credentials' method, using 'Username' and 'Password'
This is a necessary feature addition to Custom Connectors enable developers to use API authentication that have expiration on their bearer tokens, and can only be logged in via Username and Password.
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