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We are going to add 3 SAML attributes
The first attribute is "IDPEmail" and map it to: userPrincipalName.
The second attribute is "ImmutableID", use script to map it to: userID.decodeHex().encodeBase64().toString()
The third attribute is "username" and map it to: loginName.
For this attribute, Enable select "URL Path" as the location and enable the "Get Input" option
Change NameIDFormat
Now, click the "General Settings" tab
change NameIDFormat to "Map to the following attribute", and Attribute to "ImmutableID".
Finally, click "Save"
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