This feature allows you to restrict the user login based on configured domains. You can allow/deny the user login based on the email domain.
Go to your Shopify store and navigate to the Apps Section and click on Single Sign On – SSO login application.
Now go to the Setup IDP section.
Navigate to the Additional Settings section in the application dashboard and enable the Block SSO based on attributes from the IDP option.
Click on the + icon and add an attribute as shown in the below image.
If the attribute name from IDP matches the blocked attribute value, the user will be redirected to the blocked page after they SSO into the Shopify Store.
Click on Save.
For example, if the Blocked attribute's name is "domain" and its value is "@gmail.com", and you have selected the EQUALS option, all customers with a @gmail domain will be redirected to the blocked page after SSO to the Shopify Store.
If you choose NOT EQUALS, all customers who do not have a @gmail domain will be redirected to the blocked page, while customers who do have a @gmail domain will be granted access to the store.