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Create testuser2 with non-administrative privileges
Edit testuser1 Private Message settings deselecting Private Messages. The message link should not be available to other users
Create custom view with user details and add (UserID) Privatemsg: Send Privatemsg link as a field.
Login as testuser2 and browse to testuser1 custom view page.
Click the send message link. It works!
IMO, the link available to views should only display/work when the privacy setting allows this. Or; provide method to lookup value of the privacy setting field to allow custom php/jquery to hide the link.
This is preventing further development. Module disabled. Please fix.