I tried out ecomplete for email address completion today(*),
and I found it slightly annoying that when there was only a
single match for the text, I still have to firstly type M-n
to access the completion 'list', and then RET to select the
only available option.

Would the attached patch be a reasonable enhancement?


-Phil

(*) On account of 
https://www.reddit.com/r/emacs/comments/sl33w6/ecomplete_the_emacs_contact_manager_you_were/



In GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw scroll 
bars)
  of 2021-07-12 built on phil-lp
Windowing system distributor 'The X.Org Foundation', version 
11.0.12008000
System Description: Ubuntu 18.04.6 LTS