On the CASE object, using the Change Owner option in LEX.  How do I EXCLUDE users of a certain profile from appearing here?  In Classic, when I change the owner, it only displays internal users, which is what we want.  But in LEX, it displays all users, regardless of profile.  At a minimum, we would like to exclude our Community Users. 

I was pointed to this idea that says it cannot be done but some folks mention modifying the Lookup filter.  I don't see one for "Change Ownership" on the Case.  Can someone be more exact on the location to do this?

From Salesforce Support:

I have found an idea posted on an IdeaExchange forum regarding this request.

Please find the below idea link:https://trailblazer.salesforce.com/ideaView?id=0873A000000PZuoQAG

I hope this feature gets implemented soon into standard functionalities. I can understand that this is a much needed feature. As of now, using the classic version will be the best alternative.