First Inside CostOS you have to add the users inside CostOS.In that you want to. So, in the top right corner of the screen, click on Usermanagement.
It is needed to add usernames that are the same with yours domain usernames.
Then, you have to add a password. (In a future release this won't be required, so it is recommended until then, to add a strong password).
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Then you could add as many users you like to.
When Finally, when you try to login
You just have to click on SSO login.
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