I don't have any problems with Slavs or Arabs but once you start looking into the history of people and different cultures and all that you can usually tell someones heritage that way.

Slavic people look kinda like Whites with some Asian influences and Arabs look distinct but have some White features. When you see Iranians and a few other Arab groups, and I researched Arabs but it's been awhile so I could be wrong and they may not consider themselves Arabs or vise versa, but some of them look very similar to White people.

If you go back far enough and research "Aryans" and "Indo-Aryans" you can see that some of them are kinda like our distant cousins in a way.

Noticing jewish people is what started me down this road and a byproduct of that was learning about Aryans/Indo-Aryans and other cultures. It is interesting stuff and while I don't want the different races to mix and go extinct (except for jews but they can just go extinct without any mixing) I do want to see everyone keep their cultures and heritages and respect and get along with others.