[neomutt-users] tab completion on IMAP folders broken

[Richard Cobbe]

I just upgraded from neomutt 20180716 to 20200501 (I know, I'm slow), and
I'm having problems with TAB completion on IMAP folder names.  For
instance, if I'm looking at the index in my INBOX and I hit 'c', then enter
"+neo" or "=neo" and hit TAB, I just get the terminal bell, despite the
fact that I do indeed have a folder named "neomutt-users", and typing the
full folder name "=neomutt-users" works just fine.  TAB completion also
works if I try to navigate to a folder that's stored locally.

My mail provider does handle IMAP folders in a way that's a little bit
unusual, at least to me; they're all subfolders of my primary inbox.  So
I've got the following settings in my .muttrc:

    set spoolfile=imaps://rcobbe@pobox.com@mail.pobox.com/INBOX
    set folder=imaps://rcobbe@pobox.com@mail.pobox.com/INBOX

TAB completion works fine for me with this configuration on 20180716.  Did
something change in the relevant configuration in the intervening two
years?  Searching the web for "neomutt completion" doesn't turn up very
much, unfortunately.

Suggestions much appreciated!

Thanks,

Richard