I see inconsistent behavior with popup dialogs. For example, the Item Specifics dialog.
Sometime the dialog appears with no Close (x) and Maximize (+) buttons in the upper left. When this happens the dialogs automatically close when the application loses focus.
Other times the dialogs are decorated with the Close (x) and Maximize (+) buttons. When this happens the dialogs stay open when the application loses focus. It only closes when the user chooses to close it.
To me the second behavior is preferable because it makes it much faster when populating Item Specifics (Attributes) when copying data from another location into the fields.
This same inconsistent behavior is seen with other dialogs, but it is most impactful on speed of entry with Item Specifics.