bug#69987: 28.2; *mailcap shell* not in buffer list

[tom]

After switching away from *mailcap shell* buffer
there is no way to get back to it.
At least I cannot find it in the *Buffer List* buffer.
Would it be possible to keep the *mailcap shell* buffer
around as usual?  This automagical disappearance is
rather inconvenient and surprising.



In GNU Emacs 28.2 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo version 
1.16.0, Xaw3d scroll bars)
System Description: NixOS 23.05 (Stoat)

Configured using:
 'configure
 --prefix=/nix/store/5wrix9hmj9pacadlvim5gwxsdwc6321b-emacs-28.2
 --disable-build-details --with-modules --with-x-toolkit=lucid
 --with-xft --with-cairo --with-native-compilation'

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG JSON
LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES NATIVE_COMP NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
X11 XAW3D XDBE XIM XPM LUCID ZLIB

Important settings:
  value of $EMACSLOADPATH: 
  value of $EMACSNATIVELOADPATH: 
/nix/store/icpc3z2b3ix2jw2vrgp217wa40pd3hwl-emacs-packages-deps/share/emacs/native-lisp::
  value of $LANG: en_GB.UTF-8
  value of $XMODIFIERS: @im=fcitx
  locale-coding-system: utf-8-unix

Major mode: notmuch-show

Minor modes in effect:
  gpm-mouse-mode: t
  eev-mode: t
  global-git-commit-mode: t
  magit-auto-revert-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: linux
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  column-number-mode: t
  line-number-mode: t
  visual-line-mode: t
  transient-mark-mode: t

Load-path shadows:
/run/current-system/sw/share/emacs/site-lisp/site-start hides 
/nix/store/icpc3z2b3ix2jw2vrgp217wa40pd3hwl-emacs-packages-deps/share/emacs/site-lisp/site-start
/run/current-system/sw/share/emacs/site-lisp/site-start hides 
/nix/store/5wrix9hmj9pacadlvim5gwxsdwc6321b-emacs-28.2/share/emacs/site-lisp/site-start
/nix/store/icpc3z2b3ix2jw2vrgp217wa40pd3hwl-emacs-packages-deps/share/emacs/site-lisp/elpa/transient-20230602.2121/transient
 hides 
/nix/store/5wrix9hmj9pacadlvim5gwxsdwc6321b-emacs-28.2/share/emacs/28.2/lisp/transient
/nix/store/icpc3z2b3ix2jw2vrgp217wa40pd3hwl-emacs-packages-deps/share/emacs/site-lisp/elpa/let-alist-1.0.6/let-alist
 hides 
/nix/store/5wrix9hmj9pacadlvim5gwxsdwc6321b-emacs-28.2/share/emacs/28.2/lisp/emacs-lisp/let-alist

Features:
(shadow emacsbug dired-aux tramp-cmds rect pcmpl-unix org-element
avl-tree ol-eww ol-rmail ol-mhe ol-irc ol-info ol-gnus nnselect
gnus-search eieio-opt speedbar ezimage dframe gnus-art mm-uu mml2015
gnus-sum gnus-group gnus-undo gnus-start gnus-dbus dbus gnus-cloud
nnimap nnmail mail-source utf7 netrc nnoo gnus-spec gnus-int gnus-range
gnus-win ol-docview doc-view jka-compr image-mode exif ol-bibtex ol-bbdb
ol-w3m ol-doi org-link-doi mm-archive qp mailalias sendmail feedmail
sort mail-extr company-oddmuse company-keywords company-etags
company-gtags company-dabbrev-code company-dabbrev company-files
company-clang company-capf company-cmake company-semantic
company-template company-bbdb mhtml-mode css-mode smie js cc-mode
cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars
cc-defs sgml-mode facemenu gnutls network-stream url-http url-gw nsm
url-cache url-auth misearch multi-isearch find-dired mule-util rfc2104
tramp-cache tramp-sh tramp tramp-loaddefs trampver tramp-integration
files-x tramp-compat parse-time ls-lisp t-mouse term/linux psc-ide
psc-ide-protocol psc-ide-backported company elm-mode elm-interactive
elm-font-lock elm-indent-simple elm-indent elm-imenu elm-format
reformatter elm-tags elm-util pulse color let-alist f f-shortdoc
shortdoc elm-defuns bmenu watch term2 shell2 vc-git vc-dispatcher
emacs-btap ffap emacs-unoffice view org ob ob-tangle ob-ref ob-lob
ob-table ob-exp org-macro org-footnote org-src ob-comint org-pcomplete
org-list org-faces org-entities org-version ob-emacs-lisp ob-core
ob-eval org-table oc-basic bibtex iso8601 ol org-keys oc org-compat
org-macs org-loaddefs find-func emacs-pdf printing ps-print
ps-print-loaddefs ps-def lpr emacs-framebuffer eev-beginner eev-load
eev-rcirc eev-videolinks eev-audiovideo eev-wconfig eev-rstdoc
eev-helpful eev-kla eev-testblocks eev-edit eev-pdflike eejump eev-brxxx
eev-code eev-hlinks eev-tlinks eev-wrap eev-env eev-elinks eev-plinks
eev-blinks eev-template0 eev-anchors eev-codings eepitch disp-table
eev-mode eev-eval eev-multiwindow eev-flash eev-intro dumb-jump popup s
email-eww cltl clhs dict2 notmuch notmuch-tree notmuch-jump
notmuch-hello notmuch-show notmuch-print notmuch-crypto notmuch-mua
notmuch-message notmuch-draft notmuch-maildir-fcc notmuch-address
notmuch-company notmuch-parser notmuch-wash coolj goto-addr icalendar
diary-lib diary-loaddefs cal-menu calendar cal-loaddefs notmuch-tag
notmuch-lib notmuch-compat hl-line mm-view mml-smime smime dig eww-lnum
eww xdg url-queue shr kinsoku svg xml dom mm-url gnus nnheader wid-edit
magit-submodule magit-blame magit-stash magit-reflog magit-bisect
magit-push magit-pull magit-fetch magit-clone magit-remote magit-commit
magit-sequence magit-notes magit-worktree magit-tag magit-merge
magit-branch magit-reset magit-files magit-refs magit-status magit
magit-repos magit-apply magit-wip magit-log which-func imenu magit-diff
smerge-mode diff git-commit log-edit message rmc puny dired
dired-loaddefs rfc822 mml mml-sec epa derived epg rfc6068 epg-config
gnus-util rmail rmail-loaddefs time-date mm-decode mm-bodies mm-encode
mail-parse rfc2231 rfc2047 rfc2045 mm-util ietf-drums mail-prsvr
mailabbrev mail-utils gmm-utils mailheader pcvs-util add-log magit-core
magit-autorevert autorevert filenotify magit-margin magit-transient
magit-process with-editor comp comp-cstr warnings rx shell pcomplete
server magit-mode transient cl-extra help-mode magit-git magit-base
magit-section format-spec cursor-sensor crm dash compat compat-29
diff-mode paredit slime-asdf grep slime-fancy slime-indentation
slime-cl-indent cl-indent slime-trace-dialog slime-fontifying-fu
slime-package-fu slime-references slime-compiler-notes-tree advice
slime-scratch slime-presentations bridge slime-macrostep macrostep
slime-mdot-fu slime-enclosing-context slime-fancy-trace
slime-fancy-inspector slime-fuzzy slime-c-p-c slime-autodoc
slime-editing-commands slime-repl slime-parse slime apropos compile
text-property-search etags fileloop generator xref project arc-mode
archive-mode noutline outline pp comint ansi-color ring hyperspec
thingatpt picolisp tsm easy-mmode calendar2 pcase edmacro kmacro
slime-autoloads info package browse-url url url-proxy url-privacy
url-expand url-methods url-history url-cookie url-domsuf url-util
mailcap url-handlers url-parse auth-source cl-seq eieio eieio-core
cl-macs eieio-loaddefs password-cache json subr-x map url-vars seq
byte-opt gv bytecomp byte-compile cconv cl-loaddefs cl-lib iso-transl
tooltip eldoc paren electric uniquify ediff-hook vc-hooks
lisp-float-type elisp-mode mwheel term/x-win x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar
rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock
font-lock syntax font-core term/tty-colors frame minibuffer cl-generic
cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese composite emoji-zwj charscript
charprop case-table epa-hook jka-cmpr-hook help simple abbrev obarray
cl-preloaded nadvice button loaddefs faces cus-face macroexp files
window text-properties overlay sha1 md5 base64 format env code-pages
mule custom widget hashtable-print-readable backquote threads dbusbind
inotify dynamic-setting system-font-setting font-render-setting cairo
x-toolkit x multi-tty make-network-process native-compile emacs)

Memory information:
((conses 16 3685347 590674)
 (symbols 48 42598 4)
 (strings 32 377463 41688)
 (string-bytes 1 21714710)
 (vectors 16 83742)
 (vector-slots 8 2168580 192474)
 (floats 8 867 305)
 (intervals 56 629850 48218)
 (buffers 992 38))