Measured on a real linuxmintd/mint22-amd64 image and on Ubuntu 24.04. The
package installs on both, which is exactly what makes this easy to miss —
nothing on the box can then produce a stream:
* Cinnamon cannot host a virtual display (Muffin has no RecordVirtual).
* gamescope is absent from 24.04 and cannot be built for it: the tree needs
wayland >= 1.23.1 (has 1.22.0), libinput >= 1.26 (1.25), libavif >= 1.2.1
(1.0.4), pixman >= 0.44 (0.42), plus libdisplay-info2 and libxcb-errors0,
neither of which 24.04 packages at all.
* Switching desktop does not rescue it — 24.04 has KWin 5.27 (floor 6.5.6)
and GNOME Shell 46 (floor 48). Only sway 1.9 is even a candidate.
So the gamescope route documented for Cinnamon holds for LMDE 7 (Debian 13,
verified end to end) but NOT for Linux Mint 22.x — which is every mainstream
Mint until Mint 23 lands on a 26.04 base in December 2026. Both the Debian and
Ubuntu pages now say so, and the Debian page carries a per-edition table.
Also states what Debian 13 itself can drive: GNOME 48.7 and sway 1.10 are above
the floors; its KWin 6.3.6 is below.
software-properties-common is not available in Debian 13, so the
apt-add-repository line could not have worked. Debian 13 keeps its
sources in deb822 format; edit Components there instead (verified in a
trixie container — the NVIDIA driver it then offers is 550, above our
535 floor).
`punktfunk-gamescope` had never been published to the apt registry — not in any
release. It was built inside the host job's Ubuntu 24.04 image, where it cannot
build: our pin vendors wlroots 0.19.3, which floors `wayland-server` at 1.23.1,
and noble ships 1.22.0 (it also lacks libxcb-errors-dev and has only
libdisplay-info 0.1.1). Every rung of that path was a `::warning::` returning 0
and the one hard gate ran last by design, so v0.26.0 and v0.27.0 both released
with the package missing while docs-site told apt users to install it. The same
tags shipped it fine for Arch, Fedora 44 and Bazzite.
It now builds in its own job on Debian 13 (ci/gamescope-trixie.Dockerfile), the
oldest apt base the tree configures on. One package serves Debian 13 AND Ubuntu
26.04 — measured by installing and running it on both — because the build also
vendors libdisplay-info via the new `--extra-fallback` option: linked against
the distro copy it demands `libdisplay-info2` on trixie, which Ubuntu 26.04 does
not have (it carries libdisplay-info3). The option is opt-in, so the
Arch/Fedora/nix outputs are byte-for-byte unchanged. Ubuntu 24.04 gets no
gamescope package and cannot — its wayland is too old to run one however built.
Debian 13 is now a documented host target. That needed no packaging change at
all: the host .deb's glibc-2.39 floor and bundled FFmpeg already made it
installable, and it had been working for a long time while docs-site said Debian
was unsupported and unverified. Verified by installing: host, web console and
plugin runner install, resolve every soname and run. The desktop client stays
Ubuntu-26.04-only (built there, floors at `libc6 >= 2.43`; Debian 13 has 2.41).
Compositor detection now answers Cinnamon (Mint, LMDE) with the route that works
instead of advice that cannot help. Muffin forked from Mutter 3.36:
`org.cinnamon.Muffin.ScreenCast` has only RecordMonitor/RecordWindow, never
RecordVirtual, and xdg-desktop-portal-xapp implements no ScreenCast — so no
value of PUNKTFUNK_COMPOSITOR makes a Cinnamon desktop host a virtual display.
The error names headless gamescope, which needs no desktop compositor. The XDG
sniff moved into a pure function so those branches are testable; Cinnamon is
matched before GNOME, since it is a GNOME derivative and the generic arm would
otherwise hand it the Mutter backend (caught by the new test).
New `smoke-install` job installs every published package from the registry in
pristine ubuntu:24.04, ubuntu:26.04 and debian:trixie images, asserts each
binary resolves its libraries and runs, and insists the version served is the
one this run built. Nothing in deb.yml had ever installed a package it produced,
which is how both of the above survived unnoticed.
⚠ Bootstrap: seed `punktfunk-gamescope-trixie:latest` into the LAN registry once
(docker.yml builds it thereafter) or the new job cannot start.
enricobuehler