Hello,
The old method of authentication by username and password is currently outdated and is not recommended for use. More details here.
The Password grant type is a legacy way to exchange a user’s credentials for an access token. Because the client application has to collect the user’s password and send it to the authorization server, it is not recommended that this grant be used at all anymore.
But you can implement your own authentication mechanism.
Forum: Custom Authentication tip from cuba does not work in jmix
Issuer: Obtain access token programmatically · Issue #136 · jmix-projects/jmix-security · GitHub
Regards,
Nikita