Hi Team, I tried to run some tests in Mattermost Cloud to evaluate Mattermost Enterprise Edition. After setting up OIDC (OpenID Connect), I found that Mattermost tends to use the user’s email prefix as the username instead of the preferred_username provided in the OIDC Profile. Is there any way t…

Hello, @Zero While the OpenID Connect documentation does not explicitly mention if there is any possibility of configuring specific attribute for username, may I know if you are open to create a suggestion in Mattermost Uservoice ? [open_id] Let me know if you prefer me to raise it on your behalf…

Hi, @ahmaddanial I have created UserVoice suggestions. However, using the preferred_username claim as a username is part of the OIDC specification, so please consider a more standardized implementation of OIDC. Claim Name: preferred_username Claim Description: Shorthand name by which the End-Use…

Hi again, @Zero Got it and thanks for the details. I am putting the link out here for reference purposes for other users who are also interested with the same implementation of OpenID Connect: Use the preferred_username claim as the Mattermost username for OpenID Connect.

Note that these claims are only intended as hints for registration, hints for login (i.e. ask the user to provide their password etc but autofill the username/email),or potentially update details. Neither value should be leveraged for allowing users to login or determining which client account to us…

I have the same problem. Has this still not been addressed since 2021? [image] OpenID Login – Username Format Issue Hello, I have a quick technical question regarding the usernames assigned to members logging in via OpenID. Currently, when a user logs in, their usernam…

Username and OIDC integration

Troubleshooting

lemmi25 July 10, 2025, 6:43pm 6

I have the same problem. Has this still not been addressed since 2021?

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Username and OIDC integration

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