No option to configure Oauth as authentication method when selecting 'Other' in Mail Handler config

Issue Summary

This is reproducible on Data Center: (yes)

When configuring a mail handler in a JSM project, you should be able to configure OAuth as the authentication method by following the steps in Detailed steps to configure OAuth 2.0 integration with Microsoft Azure. It seems that the Mail Handler configuration page detects the list of existing links and displays them in the list based on the type (Microsoft, Gmail, other, etc.)

However, after configuring an Oauth link for a custom server, it is not possible to select that link in the JSM mail handler when selecting 'Other'. The only possible method is basic authentication.

The issue doesn't happen when configuring a Microsoft or Google link.

Steps to Reproduce

1. Configure an Oauth link for a custom server Under Administration > System > Oauth 2.0
2. Test the connection and make sure it's working.
3. Create a JSM project, then under Project settings > Email request, try to configure a mail server. Under the 'Email service provider', select 'Other'.

Expected Results

You should be able to choose the Oauth Link configured in step 1 as the authentication method.

Actual Results

The JSM mail handler configuration page doesn't display the list of possible authentication methods where you can choose the OAuth link. Instead, only basic auth is presented with user and password fields.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available.

The issue is not reproducible in JSM 5.8.1.