[Evolution] How do I save a message in a simple text file?

[Leonard Evens <len math northwestern edu>]

With previous versions of evolution, I could save a message as
something.eml.  But now the only choice is save mbox,  and I don't
understand what that does.  In any case, it seems too complicated.

So  I just copied the message contents into a text file and saved that.
But there ought to be a more direct way to do it!
-- 
Leonard Evens len math northwestern edu
Professor Emeritus, Department of Mathematics, Northwestern University