GameStream's apps.json `cmd` is delivered via set_launch_command, which ONLY the Linux
gamescope backend nests. On Windows (no gamescope) and Linux kwin/mutter/wlroots (which
stream the existing desktop) the command was silently dropped. Now, after capture is live,
stream.rs spawns it via library::launch_gamestream_command for those backends — Windows:
into the interactive USER session (spawn_in_active_session, since the host is SYSTEM);
Linux: a plain `sh -c` spawn into the host's own graphical session so the app lands on the
streamed (primary) output. Linux gamescope keeps nesting via set_launch_command and is
skipped here to avoid a double launch. The command is operator-typed apps.json (trusted),
never client-set.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
enricobuehler
7e9023faad