forked from unom/punktfunk
enricobuehlerandClaude Fable 5
a3e21d9227
First on-glass test of the DM-flavor takeover confirmed the black-screen fix, but exposed that the managed model could not switch back: Steam's in-stream session-select is a silent no-op while the display manager is stopped (every config-write branch in os-session-select requires the DM to be running), so the capture loss it causes just relaunched game mode. The user pass of the switch script does leave one durable trace — the ~/.config/steamos-session-select sentinel, written before any DM check. The managed launch now baselines its mtime; a capture loss with the sentinel advanced reads as the switch request and is honored by replaying the switch with the DM up: restore the display manager, run the distro's own os-session-select (its internal pkexec is authorized allow_any by the distro policy, so it works from the host's sessionless context), then stop the autologin game-mode unit so Relogin lands in the newly selected desktop. The capture-loss re-detection then follows KWin as it comes up; a 120 s post-honor grace stops the rebuild loop from racing the booting desktop back into game mode (superseded early if the box's own game-mode unit reappears — the desktop→game leg stays fast). The baseline is re-recorded on crash-restore so a pre-existing sentinel never reads as a fresh request. Every verb in the sequence was live-validated on the Nobara repro VM. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>