argoUML : self call has an extra return segment, doesn't seem correct, how to remove?

I'm drawing a sequence diagram in argoUML.
No question the tool is pretty good, but I'm confused if my understanding of UML is incorrect or what.

I figured how to make a self-call. However in the books the self-call has the same thing as argoUML except the return dotted line !!

The problem is that if I remove the dotted line, the block associated with it is also removed.

Here is the book version

Here is argouml's version

How do I make the regular style self-call in argouml ?

Return messages are optional (both in self and in "normal" calls). It's useful to show them when there are intermediate calls to other methods and you want to show when the initial one ends. So, both syntaxes are correct. Of course, maybe ArgoUML only uses the "extended "version