What I mean is that it is showing all users of the system - active and non active licences on the opportunity list - not on the page of a specific opportunity - how do I filter those to a specific group "active" group - such as sales people for example, so that we do not get our marketing or operations or non-active people showing up ?
Am I not mistaken that business rules work on the individual opportunity page itself, not the section ?
This logic of filtration is specified in the filters property of the lookupListConfig of the "Owner" attribute on the BaseOpportunityPage:
So in case you need to modify this filter you need to either replace the OpportunityPageV2 in the Custom package (and specify this attribute in the replaced schema) and specify new filtration for the attribute or you can override getOwnerFilter method from the PartnersOwnerMixin and add additional filtration by disabled\enabled system user. Here is also an example of the filtration based on the attribute value: https://community.creatio.com/questions/lookup-filtering-distinct-values