Hello,
Not sure if it is just an error on the help or a change in the language.
If you search for Border_Dialog on the help you are going to see that it is the default value for some classes, one of them the ModalPanel.
This is not true, ModalPanel defaults to Border_Thick.
Not sure if this occurs from DF 18.2 (there is a bug fixed for dbViews). Right now I am a bit confussed because our dialogs supports resize (they have anchors) and I don't see Border_Style explictly set to Border_Thick, so, it seem that this was the default value for a long time.
Regards.