In SPO I am creating a custom permission level with a copy of default Edit. In my custom level I am removing the Delete options, Use Self Site Creation, and Add/Remove Personal Web Parts.
Users assigned to this custom permission level then can not share documents. Testing I have found that I need to have both Self Site Creation and Add/Remove Personal Web Parts checked/included in the permission level for users to be able to share with others who do not currently have access. I have looked online and can't find a explanation for this so was wondering if others had this same issue and if anyone could explain to me why these two setting affect sharing?
I'm experiencing the same. The site permission "Edit Personal User Information" has to be enabled also. Did you find anything out about the reason? Or is anybody else here in the community able to explain it?