i noticed that you can only assign a domain to a client group within the menu "Group Managment". It is not possible to assign an entry within menü "wightlist", "blacklist" or any query list, right?
Is there a reason why this is designed by this way?
Normally in a software, a function should stay at any place.
At the moment, you have to do 2 things. First add a domain/regex from query list. In a second step, you have to search in "group management" -> "domains" for the same entry, and assign to the groups.
Menue "Adlist" is a good example for the right way. You can directly assign to a group when adding the list to pihole.