Starting 'emacs', even 'emacs -Q', from the command line (eg a Terminal session) now givesthe following warning:
You are trying to run Emacs configured with the
"pure-GTK" interface under the X Windows System. That confituration is
unsupported and will lead to sporadic crashes during transfer of large
selection data. It will also lead to various problems with keyboard
input.
Install emacs-gtk+x11 or emacs-lucid package.


But the packages are already installed:
$ sudo dnf install emacs-lucid
Fedora Core 40 - x86_64 - ATrpms                              0.0  B/s |   0  B     00:00    
Error: Failed to download metadata for repo 'atrpms': repomd.xml parser error: Parse error at line: 1 (Document is empty
)
Ignoring repositories: atrpms
Last metadata expiration check: 2:39:08 ago on Mon 13 May 2024 12:32:09 PM PDT.
Package emacs-lucid-1:29.3-6.fc40.x86_64 is already installed.
Dependencies resolved.
Nothing to do.
Complete!
$ sudo dnf install emacs-gtk+x11
Fedora Core 40 - x86_64 - ATrpms                              0.0  B/s |   0  B     00:00    
Error: Failed to download metadata for repo 'atrpms': repomd.xml parser error: Parse error at line: 1 (Document is empty
)
Ignoring repositories: atrpms
Last metadata expiration check: 2:40:57 ago on Mon 13 May 2024 12:32:09 PM PDT.
Package emacs-gtk+x11-1:29.3-6.fc40.x86_64 is already installed.
Dependencies resolved.
Nothing to do.
Complete!


This started after I upgraded to Fedora Linus 40 (Workstation Edition)
Linux alfie 6.7.10-200.fc39.x86_64 #1 SMP PREEMPT_DYNAMIC Mon Mar 18 18:56:52 UTC 2024 x86_64 GNU/Linux


Help?



In GNU Emacs 29.3 (build 1, x86_64-redhat-linux-gnu, GTK+ Version
 3.24.41, cairo version 1.18.0) of 2024-04-25 built on
 cabaf4098b994f6da8ef60f3f6652faa
System Description: Fedora Linux 40 (Workstation Edition)

Configured using:
 'configure --build=x86_64-redhat-linux-gnu
 --host=x86_64-redhat-linux-gnu --program-prefix=
 --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr
 --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc
 --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib64
 --libexecdir=/usr/libexec --localstatedir=/var --runstatedir=/run
 --sharedstatedir=/var/lib --mandir=/usr/share/man
 --infodir=/usr/share/info --with-cairo --with-dbus --with-gif
 --with-gpm=no --with-harfbuzz --with-jpeg --with-json --with-modules
 --with-native-compilation=aot --with-pgtk --with-png --with-rsvg
 --with-sqlite3 --with-tiff --with-tree-sitter --with-webp --with-xpm
 --with-xwidgets build_alias=x86_64-redhat-linux-gnu
 host_alias=x86_64-redhat-linux-gnu CC=gcc 'CFLAGS=-DMAIL_USE_LOCKF -O2
 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches
 -pipe -Wall -Werror=format-security
 -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS
 -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong
 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64
 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection
 -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer '
 LDFLAGS=-Wl,-z,relro
 PKG_CONFIG_PATH=:/usr/lib64/pkgconfig:/usr/share/pkgconfig CXX=g++
 'CXXFLAGS=-O2 -flto=auto -ffat-lto-objects -fexceptions -g
 -grecord-gcc-switches -pipe -Wall -Werror=format-security
 -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS
 -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong
 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64
 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection
 -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer ''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY
PDUMPER PGTK PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XIM XWIDGETS GTK3 ZLIB

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Info

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  isearch-fold-quotes-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  buffer-read-only: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils time-date cl-loaddefs
comp comp-cstr warnings icons subr-x rx cl-seq cl-macs gv cl-extra
help-mode bytecomp byte-compile cl-lib mule-util jka-compr info rmc
iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook
vc-hooks lisp-float-type elisp-mode mwheel term/pgtk-win pgtk-win
term/common-win pgtk-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 nadvice seq simple cl-generic indonesian philippine
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 abbrev obarray oclosure
cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp
files window text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget keymap hashtable-print-readable backquote
threads xwidget-internal dbusbind inotify dynamic-setting
system-font-setting font-render-setting cairo gtk pgtk multi-tty
make-network-process native-compile emacs)

Memory information:
((conses 16 88065 7278)
 (symbols 48 7462 0)
 (strings 32 23386 2623)
 (string-bytes 1 661792)
 (vectors 16 16249)
 (vector-slots 8 338867 12733)
 (floats 8 33 48)
 (intervals 56 575 0)
 (buffers 984 12))