Users belonging to domain A and being a member of a group created in domain B cannot access resources with the following rule:
Qlik Sense saves group name in a different format if they are from a different domain than the user.
Users that are from a different domain than the group they belong to will have the group name with the following format in Qlik Sense:CN=group1,OU=Users,DC=us,DC=domain,DC=local
This can be checked by going in the "Users" section in the QMC and clicking on the info button next to the user name.
Therefore the security should use the following rule so that all users (from the same domain and from different domains) are included:((user.group="group1" or user.group="CN=group1,OU=Users,DC=us,DC=domain,DC=local"))