Qlik Sense Stream Actions

[deec]

Does anyone have information on the different actions when creating a security rule on a stream?

Read, Update, Delete, Publish, Change Owner

I'm pretty clear on Read, but I'm wondering about the differences between the others. Say, if someone has access to Publish but not Update, will they be able to duplicate, edit and publish (with replace)? So what does update do in that case?
Why is Create grayed out?

What does Delete do? will the person who published be able to unpublish if they do not have the Delete action?

What does change owner do?

Thanks