New mail triggers view change from pager to index

[marcvs]

Expected Behaviour

When in pager mode, I'm reading (possibly long) emails. Newer versions of neomutt will jump back to index mode, whenver a new email appears in my filesystem (I'm using mbsync).

I didn't switch away from NeoMutt/20180716 for that reason.

Steps to Reproduce

1. Open an email.
2. Receive a new one (use a local Mailfolder, use mbsync)
3. Watch mutt switch to index

How often

• Always

When did it start to happen?

• When I upgraded
  • Working version: 20180716
  • Not working version: 20200925 (I tried upgrading earlier, but didn't, due to this. I guess that was in march)

NeoMutt Version

NeoMutt 20200925
Copyright (C) 1996-2020 Michael R. Elkins and others.
NeoMutt comes with ABSOLUTELY NO WARRANTY; for details type 'neomutt -vv'.
NeoMutt is free software, and you are welcome to redistribute it
under certain conditions; type 'neomutt -vv' for details.

System: Linux 5.7.0-1-amd64 (x86_64)
ncurses: ncurses 6.2.20200918 (compiled with 6.2.20200918)
libidn: 1.33 (compiled with 1.33)
GPGME: 1.14.0-unknown
GnuTLS: 3.6.15
storage: kyotocabinet

Configure options: --prefix=/usr --libexecdir=/usr/lib --libdir=/usr/lib --enable-nls --gpgme --sasl --gnutls --ssl --kyotocabinet --disable-doc

Compilation CFLAGS: -g -O2 -std=c99 -D_ALL_SOURCE=1 -D_GNU_SOURCE=1 -D__EXTENSIONS__ -I/usr/include -DNCURSES_WIDECHAR

Default options:
  +attach_headers_color +compose_to_sender +compress +cond_date +debug 
  +encrypt_to_self +forgotten_attachments +forwref +ifdef +imap +index_color 
  +initials +limit_current_thread +multiple_fcc +nested_if +new_mail +nntp +pop 
  +progress +quasi_delete +regcomp +reply_with_xorig +sensible_browser +sidebar 
  +skip_quoted +smtp +status_color +timeout +tls_sni +trash 

Compile options:
  -autocrypt +bkgdset +color +curs_set +fcntl -flock -fmemopen +futimens 
  +getaddrinfo +gnutls +gpgme -gss +hcache -homespool +idn +inotify 
  -locales_hack -lua +meta -mixmaster +nls -notmuch -openssl +pgp +regex +sasl 
  +smime -sqlite +start_color +sun_attachment +typeahead 
MAILPATH="/var/mail"
PKGDATADIR="/usr/share/neomutt"
SENDMAIL="/usr/sbin/sendmail"
SYSCONFDIR="/etc"

To learn more about NeoMutt, visit: https://neomutt.org
If you find a bug in NeoMutt, please raise an issue at:
    https://github.com/neomutt/neomutt/issues
or send an email to: <neomutt-devel@neomutt.org>

Extra Info

• Operating System and its version:
  • debian-10 (bullseye/sid)
• Were you using multiple copies of NeoMutt at once?
  • Sure :) I'm compiling from different folders with a different branch of git, using
• Were you using 'screen' or 'tmux'?
  • No
• Is your email local (maildir) or remote (IMAP)?
  • maildir

[liskin]

Not only does it jump back to the index mode, it also messes up what neomutt thinks is the current message. Once this happens, reading an e-mail thread is almost impossible as ↑/↓ arrows jump to seemingly random locations in the mailbox. So every time I receive an e-mail while reading another one, I have to change folder or restart mutt.

I have a feeling this might be somehow related to #2091 as the workaround there is to also exit pager mode before doing anything.