extra packages depending on community were, as far as I know, *never* enforced (or at least not for many many years). I fully expect hundreds of problems exactly like this one, and I wouldn't be remotely surprised if the full count is in the thousands.

Assuming for the sake of argument that this is a legitimate issue (I sympathize, but it seems to not actually be a concern of... pretty much anyone), this still isn't very useful as a bug report because what we actually need is a massive TODO list and a coordinated full repository cleanup/reorganization.

Submitting the occasional bug here and there to solve a very small minority of packages is frankly a waste of time; it's the least efficient way to solve the problem, and it doesn't fulfill the objective of cleanly separating extra and community.

When we have general repository issues that involve many packages at once, we never submit individual bugs for them, we always create TODO lists.

I'd be more interested in the idea of going through the entire repository and formulating a proper list of actionable packages, then handling all of them...

Retitling for clarity.

I encountered the issue when I tried to disable the community repository in systemd's mkosi (https://github.com/systemd/mkosi) tool to save a little time on synchronization. I agree that this wouldn't be a real fix. I checked my own installed list of packages from community and immediately found more examples of packages from extra depending on packages from community.

Without actually looking into it, it should be doable to script the finding of offending packages and create a TODO list. If I manage to find the time to make a TODO list, where would I submit it?

Exact numbers are good, there are 192 missing package dependencies if you enable only core and extra. This doesn't count recursive issues, so moving some of these packages to extra might "unlock" further errors.

$ pacman --config /etc/pacman.d/pacman-extra.conf -Dkk
error: missing 'python-argcomplete' dependency for '389-ds-base'
error: missing 'python-dateutil' dependency for '389-ds-base'
error: missing 'python-ldap' dependency for '389-ds-base'
error: missing 'ipython' dependency for 'accerciser'
error: missing 'python-xlib' dependency for 'accerciser'
error: missing 'python-click' dependency for 'arch-signoff'
error: missing 'python-dateutil' dependency for 'arch-signoff'
error: missing 'isdn4k-utils>=3.20-1' dependency for 'archboot'
error: missing 'squashfs-tools>=4.2-2' dependency for 'archboot'
error: missing 'weechat>=0.3.7-1' dependency for 'archboot'
error: missing 'chntpw>=110511-2' dependency for 'archboot'
error: missing 'arch-wiki-lite>=20120619-1' dependency for 'archboot'
error: missing 'arch-wiki-lite>=20120619-1' dependency for 'archboot'
error: missing 'cpupower>=3.5-4' dependency for 'archboot'
error: missing 'wvdial>=1.61-4' dependency for 'archboot'
error: missing 'xl2tpd>=1.3.0-2' dependency for 'archboot'
error: missing 'usb_modeswitch>=1.2.4-1' dependency for 'archboot'
error: missing 'refind-efi>=0.4.5-1' dependency for 'archboot'
error: missing 'exfat-utils>=1.2.4-1' dependency for 'archboot'
error: missing 'broadcom-wl' dependency for 'archboot'
error: missing 'squashfs-tools' dependency for 'archiso'
error: missing 'hardlink' dependency for 'archivetools'
error: missing 'jq' dependency for 'asp'
error: missing 'hdf5' dependency for 'avogadrolibs'
error: missing 'libmaxminddb' dependency for 'bind'
error: missing 'libmaxminddb' dependency for 'bind-tools'
error: missing 'cdrtools' dependency for 'brasero'
error: missing 'python-configobj' dependency for 'breezy'
error: missing 'python-dulwich' dependency for 'breezy'
error: missing 'isdn4k-utils' dependency for 'capi4hylafax'
error: missing 'ttf-liberation' dependency for 'chromium'
error: missing 'perl-gtk3' dependency for 'clawsker'
error: missing 'jansson' dependency for 'ctags'
error: missing 'python-rencode>=1.0.2' dependency for 'deluge'
error: missing 'python-setproctitle' dependency for 'deluge'
error: missing 'python-pillow' dependency for 'deluge'
error: missing 'python-distro' dependency for 'deluge'
error: missing 'cdrkit' dependency for 'dvd+rw-tools'
error: missing 'opusfile' dependency for 'easytag'
error: missing 'luajit' dependency for 'efl'
error: missing 'libhandy' dependency for 'epiphany'
error: missing 'libmfx' dependency for 'ffmpeg'
error: missing 'vmaf' dependency for 'ffmpeg'
error: missing 'tepl' dependency for 'gedit'
error: missing 'libgexiv2' dependency for 'gegl'
error: missing 'luajit' dependency for 'gegl'
error: missing 'gtkspell3' dependency for 'gitg'
error: missing 'python-jedi' dependency for 'gnome-builder'
error: missing 'autoconf-archive' dependency for 'gnome-builder'
error: missing 'python-sphinx' dependency for 'gnome-builder'
error: missing 'libhandy' dependency for 'gnome-clocks'
error: missing 'autoconf-archive' dependency for 'gnome-common'
error: missing 'libhandy' dependency for 'gnome-contacts'
error: missing 'bolt' dependency for 'gnome-control-center'
error: missing 'libhandy' dependency for 'gnome-control-center'
error: missing 'libhandy' dependency for 'gnome-notes'
error: missing 'libgexiv2' dependency for 'gnome-photos'
error: missing 'libhandy' dependency for 'gnome-tweaks'
error: missing 'frei0r-plugins' dependency for 'gnome-video-effects'
error: missing 'python-markdown' dependency for 'gobject-introspection'
error: missing 'libfdk-aac' dependency for 'gst-plugins-bad'
error: missing 'liblrdf' dependency for 'gst-plugins-bad'
error: missing 'lilv' dependency for 'gst-plugins-bad'
error: missing 'twolame' dependency for 'gst-plugins-good'
error: missing 'python-pygments' dependency for 'gtk-doc'
error: missing 'libnfs' dependency for 'gvfs-nfs'
error: missing 'ninja' dependency for 'gyp'
error: missing 'python-distro' dependency for 'hplip'
error: missing 'python-pyenchant' dependency for 'ibus-typing-booster'
error: missing 'gtkspell3' dependency for 'inkscape'
error: missing 'vtk' dependency for 'kalzium'
error: missing 'python-jinja' dependency for 'kapidox'
error: missing 'python-yaml' dependency for 'kapidox'
error: missing 'libfakekey' dependency for 'kdeconnect'
error: missing 'kpeoplevcard' dependency for 'kdeconnect'
error: missing 'frei0r-plugins' dependency for 'kdenlive'
error: missing 'python-pyserial' dependency for 'kismet'
error: missing 'hidapi' dependency for 'libfido2'
error: missing 'goocanvas' dependency for 'libgda'
error: missing 'hidapi' dependency for 'libnitrokey'
error: missing 'jansson' dependency for 'libnm'
error: missing 'lua52-socket' dependency for 'libquvi-scripts'
error: missing 'lua52-bitop' dependency for 'libquvi-scripts'
error: missing 'lua52-expat' dependency for 'libquvi-scripts'
error: missing 'brotli' dependency for 'libsoup'
error: missing 'jansson' dependency for 'libteam'
error: missing 'zeromq' dependency for 'libteam'
error: missing 'libftdi' dependency for 'lirc'
error: missing 'ninja' dependency for 'meson'
error: missing 'isdn4k-utils' dependency for 'misdnuser'
error: missing 'cdrkit' dependency for 'mkisolinux'
error: missing 'msgpack-c' dependency for 'mmtf-cpp'
error: missing 'libnfs' dependency for 'mpd'
error: missing 'twolame' dependency for 'mpd'
error: missing 'libreplaygain' dependency for 'musepack-tools'
error: missing 'libgexiv2' dependency for 'nautilus'
error: missing 'libnewt' dependency for 'networkmanager'
error: missing 'jansson' dependency for 'nftables'
error: missing 'libev' dependency for 'nghttp2'
error: missing 'jansson' dependency for 'nghttp2'
error: missing 'jansson' dependency for 'nvidia-settings'
error: missing 'pcsclite' dependency for 'openconnect'
error: missing 'perl-file-chdir' dependency for 'perl-alien-build'
error: missing 'perl-path-tiny' dependency for 'perl-alien-build'
error: missing 'perl-canary-stability' dependency for 'perl-async-interrupt'
error: missing 'perl-path-class' dependency for 'perl-crypt-ssleay'
error: missing 'perl-json' dependency for 'perl-mail-authenticationresults'
error: missing 'perl-yaml-libyaml' dependency for 'perl-mail-dkim'
error: missing 'perl-xml-sax-expat' dependency for 'perl-xml-simple'
error: missing 'oniguruma' dependency for 'php'
error: missing 'libsodium' dependency for 'php-sodium'
error: missing 'bolt' dependency for 'plasma-thunderbolt'
error: missing 'python-pytz' dependency for 'python-django'
error: missing 'python-sqlparse' dependency for 'python-django'
error: missing 'python-click' dependency for 'python-incremental'
error: missing 'python-toml' dependency for 'python-pep517'
error: missing 'python-cachecontrol' dependency for 'python-pip'
error: missing 'python-colorama' dependency for 'python-pip'
error: missing 'python-contextlib2' dependency for 'python-pip'
error: missing 'python-distlib' dependency for 'python-pip'
error: missing 'python-distro' dependency for 'python-pip'
error: missing 'python-html5lib' dependency for 'python-pip'
error: missing 'python-msgpack' dependency for 'python-pip'
error: missing 'python-progress' dependency for 'python-pip'
error: missing 'python-pytoml' dependency for 'python-pip'
error: missing 'python-webencodings' dependency for 'python-pip'
error: missing 'python-pynacl' dependency for 'python-pymacaroons'
error: missing 'python-pytest' dependency for 'python-pytest-qt'
error: missing 'python-isodate' dependency for 'python-rdflib'
error: missing 'python-pyhamcrest' dependency for 'python-twisted'
error: missing 'python-distlib' dependency for 'python-virtualenv'
error: missing 'python-filelock' dependency for 'python-virtualenv'
error: missing 'python2-singledispatch' dependency for 'python2-astroid'
error: missing 'python2-enum34' dependency for 'python2-astroid'
error: missing 'python2-enum34' dependency for 'python2-cryptography'
error: missing 'python2-click' dependency for 'python2-incremental'
error: missing 'python2-futures' dependency for 'python2-isort'
error: missing 'python2-toml' dependency for 'python2-pep517'
error: missing 'python2-importlib-metadata' dependency for 'python2-pep517'
error: missing 'python2-zipp' dependency for 'python2-pep517'
error: missing 'python2-cachecontrol' dependency for 'python2-pip'
error: missing 'python2-colorama' dependency for 'python2-pip'
error: missing 'python2-contextlib2' dependency for 'python2-pip'
error: missing 'python2-distlib' dependency for 'python2-pip'
error: missing 'python2-distro' dependency for 'python2-pip'
error: missing 'python2-html5lib' dependency for 'python2-pip'
error: missing 'python2-msgpack' dependency for 'python2-pip'
error: missing 'python2-progress' dependency for 'python2-pip'
error: missing 'python2-pytoml' dependency for 'python2-pip'
error: missing 'python2-webencodings' dependency for 'python2-pip'
error: missing 'python2-singledispatch' dependency for 'python2-pylint'
error: missing 'python2-enum34' dependency for 'python2-pyqt5'
error: missing 'python2-pyhamcrest' dependency for 'python2-twisted'
error: missing 'python2-distlib' dependency for 'python2-virtualenv'
error: missing 'python2-filelock' dependency for 'python2-virtualenv'
error: missing 'python2-contextlib2' dependency for 'python2-virtualenv'
error: missing 'python2-importlib-metadata' dependency for 'python2-virtualenv'
error: missing 'python2-importlib_resources' dependency for 'python2-virtualenv'
error: missing 'python2-pathlib2' dependency for 'python2-virtualenv'
error: missing 'libnfs' dependency for 'qemu'
error: missing 'usbredir' dependency for 'qemu'
error: missing 'libslirp' dependency for 'qemu'
error: missing 'glusterfs' dependency for 'qemu-block-gluster'
error: missing 'ceph-libs' dependency for 'qemu-block-rbd'
error: missing 'libnfs' dependency for 'qemu-headless'
error: missing 'usbredir' dependency for 'qemu-headless'
error: missing 'libslirp' dependency for 'qemu-headless'
error: missing 'yaml-cpp' dependency for 'qtcreator'
error: missing 'libmanette' dependency for 'quadrapassel'
error: missing 'ruby-irb' dependency for 'ruby'
error: missing 'perl-parse-yapp' dependency for 'samba'
error: missing 'ceph-libs' dependency for 'samba'
error: missing 'opusfile' dependency for 'sdl2_mixer'
error: missing 'libhandy' dependency for 'seahorse'
error: missing 'python-toml' dependency for 'sip5'
error: missing 'jansson' dependency for 'smbclient'
error: missing 'gpsd' dependency for 'stellarium'
error: missing 'libutf8proc' dependency for 'subversion'
error: missing 'libiptcdata' dependency for 'tracker-miners'
error: missing 'libosinfo' dependency for 'tracker-miners'
error: missing 'libgexiv2' dependency for 'tracker-miners'
error: missing 'libqb' dependency for 'usbguard'
error: missing 'libqb.so=0-64' dependency for 'usbguard'
error: missing 'libsodium' dependency for 'usbguard'
error: missing 'spice-gtk3' dependency for 'vinagre'
error: missing 'freerdp' dependency for 'vinagre'
error: missing 'brotli' dependency for 'woff2'
error: missing 'pwgen' dependency for 'x2goserver'
error: missing 'sshfs' dependency for 'x2goserver'
error: missing 'perl-switch' dependency for 'x2goserver'
error: missing 'polkit-gnome' dependency for 'xfce4-session'
error: missing 'libxpresent' dependency for 'xfwm4'

Also cross-reference core depending on extra:  FS#64415   FS#64037   FS#64416 

And to complete the set, I submitted  FS#66712  -- core is mostly not an issue, so there's only a small handful of issues.