fix(gamescope): ship a packaged privilege path for the DM-stop takeover

Field report (Nobara, 0.19.2): entering Game Mode mid-stream left the monitor
on and the stream mirroring at the desktop's resolution. Root cause: the
DM-flavor takeover needs privilege to stop plasmalogin, the polkit rule is a
docs-only manual step nobody installs, so every managed entry silently
degraded to ATTACH — and with a physical display connected the attach path
mirrors the box's own session at its own mode.

Ship the privilege with the packages instead: a root helper
(libexec/punktfunk/pf-dm-helper, verbs stop|restore) behind its own polkit
action (io.unom.punktfunk.dm-helper, allow_any — the same mechanism Nobara's
os-session-select uses, and the helper derives the DM unit from the
display-manager.service symlink itself so callers never name a unit across
the privilege boundary). The host tries the plain system-bus verbs first
(root / operator rule still take precedence), then pkexec's the helper; the
restore paths (idle restore + in-stream desktop-switch honor) use the same
ladder so a takeover that needed the helper can always be undone by it.

Packaged in rpm/deb/arch (Arch under /usr/lib/punktfunk with the policy's
exec.path annotation rewritten; the host probes both layouts). Nix is left
out deliberately: store paths can't match the probe, NixOS keeps the manual
rule. Docs updated — the rule snippet stays as the scoped alternative.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/pf-capture/src/linux/mod.rs

@@ -2652,6 +2652,18 @@ mod pipewire {
             build_default_format_obj(preferred)
         };
 
+        // gamescope trap — the Steam overlay's presence in the stream is decided HERE by omission:
+        // gamescope's `paint_pipewire()` composites the overlay (Shift+Tab / Quick Access Menu) into
+        // the node it hands us ONLY when the consumer-negotiated `gamescope_focus_appid` is 0 — the
+        // default, and the "mirror the focused window + overlay" branch (gamescope ≥ 3.16.23; see
+        // `MIN_GAMESCOPE_OVERLAY`). None of the EnumFormat pods below advertise the
+        // `SPA_FORMAT_VIDEO_gamescope_focus_appid` property, so gamescope reads 0 and paints the
+        // overlay for us for free. DO NOT add a non-zero focus-appid (e.g. to "isolate the game" in a
+        // dedicated session) — that flips gamescope into the Remote-Play branch that deliberately
+        // drops the overlay (and all host chrome) back out of the capture. The cursor, external
+        // overlay (MangoHUD), and notifications are excluded from the node on EVERY gamescope
+        // version and are composited host-side instead (see `xfixes_cursor.rs`).
+        //
         // When zero-copy is on, offer ONLY a BGRx dmabuf format with our EGL-importable modifiers
         // (offering shm too makes the compositor pick shm). The modifier list is advertised with
         // DONT_FIXATE so the compositor's allocator chooses one; we re-emit the fixated format in

crates/pf-vdisplay/src/vdisplay/linux/gamescope.rs

@@ -1139,18 +1139,67 @@ fn dm_survives_masked_unit(dm: &str) -> bool {
     dm == "sddm.service"
 }
 
-/// Stop the display manager for a takeover on a mask-fragile DM flavor. Plain `systemctl stop` on
-/// the SYSTEM bus — succeeds as root or under an operator polkit rule scoped to the DM unit (see
-/// docs); fails cleanly otherwise ("interactive authentication required"), in which case the
-/// caller degrades to attach.
-fn try_stop_display_manager(dm: &str) -> bool {
-    Command::new("systemctl")
-        .args(["stop", dm])
+/// The packaged privileged fallback for the display-manager takeover verbs: a root helper behind
+/// its own polkit action (`io.unom.punktfunk.dm-helper`, `allow_any` — the mechanism these
+/// distros use for their own session switcher, e.g. Nobara's `os-session-select`), so the managed
+/// takeover works out of the box on mask-fragile DM flavors with no hand-installed polkit rule.
+/// The helper derives the DM unit from the `display-manager.service` symlink itself, so this
+/// process never gets to name an arbitrary unit across the privilege boundary. Two layouts: the
+/// rpm/deb `libexec` path (what the shipped policy annotates) and Arch's `/usr/lib/<pkg>` (its
+/// PKGBUILD rewrites the annotation to match).
+const DM_HELPER_PATHS: &[&str] = &[
+    "/usr/libexec/punktfunk/pf-dm-helper",
+    "/usr/lib/punktfunk/pf-dm-helper",
+];
+
+/// Run the packaged DM helper (`stop` | `restore`) via pkexec. `false` when the helper isn't
+/// installed (tarball/old package), pkexec is missing, or polkit denies the action.
+fn dm_helper(verb: &str) -> bool {
+    let Some(helper) = DM_HELPER_PATHS
+        .iter()
+        .find(|p| std::path::Path::new(p).exists())
+    else {
+        return false;
+    };
+    Command::new("pkexec")
+        .arg(helper)
+        .arg(verb)
         .status()
         .map(|s| s.success())
         .unwrap_or(false)
 }
 
+/// Stop the display manager for a takeover on a mask-fragile DM flavor. Plain `systemctl stop` on
+/// the SYSTEM bus first — succeeds as root or under an operator polkit rule scoped to the DM unit
+/// (see docs); fails cleanly otherwise ("interactive authentication required") — then the
+/// packaged pkexec helper. `false` means no privilege path exists and the caller degrades to
+/// attach.
+fn try_stop_display_manager(dm: &str) -> bool {
+    let direct = Command::new("systemctl")
+        .args(["stop", dm])
+        .status()
+        .map(|s| s.success())
+        .unwrap_or(false);
+    direct || dm_helper("stop")
+}
+
+/// Restore the display manager: `reset-failed` (a relogin loop may have tripped the unit's start
+/// limit, and a plain restart is refused until the accounting clears) + `restart` — its autologin
+/// session Exec brings the box's own session back up. Plain system-bus verbs first (root / an
+/// operator polkit rule), then the packaged pkexec helper, whose `restore` verb performs the same
+/// two steps as root.
+fn restore_display_manager(dm: &str) -> bool {
+    let _ = Command::new("systemctl")
+        .args(["reset-failed", dm])
+        .status();
+    let direct = Command::new("systemctl")
+        .args(["restart", dm])
+        .status()
+        .map(|s| s.success())
+        .unwrap_or(false);
+    direct || dm_helper("restore")
+}
+
 /// The distro's session-switch helper (ChimeraOS/Nobara layout). Its USER pass records the
 /// sentinel + self-pkexecs (authorized `allow_any` by the distro's own polkit action policy, so
 /// it works from our sessionless context); its ROOT pass rewrites the DM autologin config — but
@@ -1219,10 +1268,13 @@ fn honor_session_select_switch(dm: String) {
     clear_takeover();
     *MANAGED_SESSION.lock().unwrap_or_else(|e| e.into_inner()) = None;
     stop_session(SESSION_UNIT); // dead already (the switch shut its Steam down) — clear the unit
-    let _ = Command::new("systemctl")
-        .args(["reset-failed", &dm])
-        .status();
-    let _ = Command::new("systemctl").args(["start", &dm]).status();
+    if !restore_display_manager(&dm) {
+        tracing::warn!(
+            %dm,
+            "gamescope: display-manager start was denied — the desktop switch may need a manual \
+             `systemctl restart` of the DM"
+        );
+    }
     let deadline = Instant::now() + Duration::from_secs(10);
     while Instant::now() < deadline {
         let active = Command::new("systemctl")
@@ -1343,8 +1395,10 @@ fn stop_autologin_sessions() -> Result<()> {
         if !try_stop_display_manager(&dm) {
             bail!(
                 "the box's gaming session is driven by {dm}, which does not survive a masked \
-                 session unit, and stopping it needs privilege — install the punktfunk \
-                 display-manager polkit rule (see docs) to enable the managed takeover"
+                 session unit, and stopping it needs privilege — the packaged pf-dm-helper \
+                 polkit action is missing or was denied (reinstall the punktfunk package, or \
+                 install the display-manager polkit rule from the docs) so the managed takeover \
+                 is unavailable"
             );
         }
         tracing::info!(
@@ -1668,14 +1722,7 @@ fn do_restore_tv_session() {
     // (`reset-failed` clears the relogin start-limit accounting, then `restart`); its autologin
     // session Exec starts the gamescope unit itself.
     if let Some(dm) = dm {
-        let _ = Command::new("systemctl")
-            .args(["reset-failed", &dm])
-            .status();
-        let restart = Command::new("systemctl")
-            .args(["restart", &dm])
-            .status()
-            .map(|s| s.success())
-            .unwrap_or(false);
+        let restart = restore_display_manager(&dm);
         if restart {
             tracing::info!(%dm, "restored the display manager (its autologin brings gaming mode back)");
         } else if crate::try_recover_session() {

crates/pf-vdisplay/src/vdisplay/linux/gamescope/discovery.rs

@@ -340,9 +340,19 @@ pub(crate) fn is_available() -> bool {
 /// against PipeWire ≥ 1.6 (a loop-lock bug) and a stuck link head-blocks the whole daemon.
 const MIN_GAMESCOPE: (u32, u32, u32) = (3, 16, 22);
 
-/// Best-effort: warn loudly if the installed gamescope is older than [`MIN_GAMESCOPE`]. Parsing
-/// failures are silent (don't block a possibly-fine custom build) — this is a diagnostic, not a
-/// gate. Returns the parsed version when it could read one.
+/// First gamescope that paints the Steam overlay (Shift+Tab / Quick Access Menu) into its built-in
+/// PipeWire node. `paint_pipewire()` is a *separate, reduced* composite from the display scanout;
+/// the overlay-window paint (gated on the consumer negotiating `gamescope_focus_appid == 0`, which
+/// we do by never advertising that property — see the capturer's EnumFormat builders) first ships
+/// in 3.16.23 (gamescope commits `ccd62074` + `f8b33d38`). Below this the overlay is *never* in the
+/// node, so it cannot appear in the stream no matter what the host does. The cursor and
+/// external-overlay / notification layers are excluded on *every* version (handled host-side).
+const MIN_GAMESCOPE_OVERLAY: (u32, u32, u32) = (3, 16, 23);
+
+/// Best-effort: warn if the installed gamescope is older than [`MIN_GAMESCOPE`] (capture is
+/// unreliable) or than [`MIN_GAMESCOPE_OVERLAY`] (capture works but the Steam overlay can't reach
+/// the stream). Parsing failures are silent (don't block a possibly-fine custom build) — this is a
+/// diagnostic, not a gate. Returns the parsed version when it could read one.
 pub(super) fn check_gamescope_version() -> Option<(u32, u32, u32)> {
     let out = Command::new("gamescope").arg("--version").output().ok()?;
     // gamescope prints the version banner to stderr on some builds, stdout on others.
@@ -360,6 +370,18 @@ pub(super) fn check_gamescope_version() -> Option<(u32, u32, u32)> {
              capture deadlock against PipeWire ≥ 1.6 (a wedged link head-blocks the daemon); \
              upgrade gamescope or use PUNKTFUNK_COMPOSITOR=kwin|mutter"
         );
+    } else if ver < MIN_GAMESCOPE_OVERLAY {
+        // Capture is fine; the Steam overlay just won't be in the frame gamescope hands us.
+        tracing::warn!(
+            found = %format!("{}.{}.{}", ver.0, ver.1, ver.2),
+            min = %format!(
+                "{}.{}.{}",
+                MIN_GAMESCOPE_OVERLAY.0, MIN_GAMESCOPE_OVERLAY.1, MIN_GAMESCOPE_OVERLAY.2
+            ),
+            "gamescope is older than the first version that paints the Steam overlay (Shift+Tab / \
+             Quick Access Menu) into its PipeWire node — the overlay will be absent from the \
+             stream until you upgrade gamescope (the cursor is composited host-side regardless)"
+        );
     }
     Some(ver)
 }
@@ -379,7 +401,7 @@ fn parse_version(text: &str) -> Option<(u32, u32, u32)> {
 
 #[cfg(test)]
 mod tests {
-    use super::{parse_version, steam_appid_from_launch, MIN_GAMESCOPE};
+    use super::{parse_version, steam_appid_from_launch, MIN_GAMESCOPE, MIN_GAMESCOPE_OVERLAY};
 
     #[test]
     fn parses_steam_appid_from_launch() {
@@ -425,4 +447,15 @@ mod tests {
         assert!(parse_version("gamescope version 3.16.22").unwrap() >= MIN_GAMESCOPE);
         assert!(parse_version("gamescope version 3.17.0").unwrap() >= MIN_GAMESCOPE);
     }
+
+    #[test]
+    fn overlay_threshold_brackets_the_fix() {
+        // 3.16.22 captures fine but predates the overlay-in-pipewire paint — it sits in the
+        // "capture works, overlay absent" window `[MIN_GAMESCOPE, MIN_GAMESCOPE_OVERLAY)`, which is
+        // exactly the `else if` warn arm; 3.16.23 is the first to include the overlay.
+        assert!(parse_version("gamescope version 3.16.22").unwrap() >= MIN_GAMESCOPE);
+        assert!(parse_version("gamescope version 3.16.22").unwrap() < MIN_GAMESCOPE_OVERLAY);
+        assert!(parse_version("gamescope version 3.16.23").unwrap() >= MIN_GAMESCOPE_OVERLAY);
+        assert!(parse_version("gamescope version 3.16.25").unwrap() >= MIN_GAMESCOPE_OVERLAY);
+    }
 }

crates/punktfunk-host/src/windows/install.rs

@@ -431,16 +431,69 @@ fn web_setup(args: &[String]) -> Result<()> {
     ) {
         eprintln!("warning: could not add the firewall rule for TCP 47992");
     }
-    // 5. wait briefly for the host's mgmt token, then start (restart-on-failure picks it up otherwise)
-    for _ in 0..30 {
-        if token_path.exists() {
-            break;
+    // 5. Wait for EVERY file the launcher needs, then start the task and VERIFY it came up.
+    //
+    //    `web-run.cmd` refuses to serve without the mgmt token AND the host identity cert, and the
+    //    host writes them in that order: the token during argument parsing (`main::parse_serve`,
+    //    milliseconds after `serve` starts), the cert only once `serve` reaches
+    //    `gamestream::cert::ServerIdentity::load_or_create` - behind a pure-Rust RSA-2048 keygen
+    //    whose prime search has a multi-second tail. Gating on the token alone therefore fired
+    //    `schtasks /run` while that keygen was still running: the launcher exited 1, and since the
+    //    task carries no trigger other than boot (and Task Scheduler's restart-on-failure does not
+    //    reliably fire for a plain non-zero exit code), a freshly installed console stayed down
+    //    until the next reboot. Gate on `cert.pem` - written LAST, after `key.pem` - so all three
+    //    files are on disk before the first start.
+    let cert_path = data_dir.join("cert.pem");
+    if !wait_for_files(&[token_path.as_path(), cert_path.as_path()], 90) {
+        eprintln!(
+            "warning: the host service has not written {} + {} yet - not starting the console now; \
+             it will start at the next boot (or run: schtasks /run /tn {WEB_TASK})",
+            token_path.display(),
+            cert_path.display()
+        );
+        println!("web console set up (https://<host-ip>:47992)");
+        return Ok(());
+    }
+    if start_web_task() {
+        println!("web console set up + started (https://<host-ip>:47992)");
+    } else {
+        // Never claim "started" when it isn't: the launcher's own diagnostics go to a task with no
+        // console, so this warning is the only trace an operator gets at install time.
+        eprintln!(
+            "warning: the {WEB_TASK} task did not bring up a listener on :47992 - check its Last Run \
+             Result in Task Scheduler; the console will be retried at the next boot"
+        );
+        println!("web console set up (https://<host-ip>:47992)");
+    }
+    Ok(())
+}
+
+/// Poll until every path exists, or `secs` elapse. Returns whether they all showed up.
+fn wait_for_files(paths: &[&Path], secs: u64) -> bool {
+    for _ in 0..secs {
+        if paths.iter().all(|p| p.exists()) {
+            return true;
         }
         std::thread::sleep(std::time::Duration::from_secs(1));
     }
+    paths.iter().all(|p| p.exists())
+}
+
+/// `schtasks /run` + verify: the command reports only that a start was *attempted*, so poll for the
+/// console's own listener and retry a couple of times before giving up. Returns whether :47992 ended
+/// up listening.
+fn start_web_task() -> bool {
+    for _ in 0..3 {
         run_quiet("schtasks", &["/run", "/tn", WEB_TASK]);
-    println!("web console set up + started (https://<host-ip>:47992)");
-    Ok(())
+        // Bun binds the port a second or two after launch on a warm box; allow for a cold one.
+        for _ in 0..10 {
+            std::thread::sleep(std::time::Duration::from_secs(1));
+            if !web_listener_pids().is_empty() {
+                return true;
+            }
+        }
+    }
+    false
 }
 
 /// Source: a non-empty `--password-file` (fresh install) > keep existing (upgrade) > random fallback.
@@ -505,30 +558,57 @@ fn random_password() -> String {
 /// ("LISTENING"/"ABHOEREN"/...) is never parsed.
 fn stop_web_console() {
     run_quiet("schtasks", &["/end", "/tn", WEB_TASK]);
-    for line in run_capture("netstat", &["-ano", "-p", "tcp"]).lines() {
-        let toks: Vec<&str> = line.split_whitespace().collect();
-        if toks.len() >= 5
-            && toks[0].eq_ignore_ascii_case("tcp")
-            && toks[1].ends_with(":47992")
-            && (toks[2] == "0.0.0.0:0" || toks[2] == "[::]:0")
-        {
-            let pid = toks[toks.len() - 1];
-            if !pid.is_empty() && pid.bytes().all(|b| b.is_ascii_digit()) {
-                run_quiet("taskkill", &["/PID", pid, "/F"]);
-            }
-        }
+    for pid in web_listener_pids() {
+        run_quiet("taskkill", &["/PID", &pid, "/F"]);
     }
     std::thread::sleep(std::time::Duration::from_secs(1));
 }
 
-/// Register the boot/SYSTEM/restart-on-failure task via a generated Task Scheduler XML (`schtasks /xml`,
-/// no COM). The XML declares UTF-16, so it's written UTF-16LE+BOM.
+/// PIDs owning a LISTEN socket on :47992. Also the console's liveness probe (`start_web_task`).
+fn web_listener_pids() -> Vec<String> {
+    run_capture("netstat", &["-ano", "-p", "tcp"])
+        .lines()
+        .filter_map(|line| {
+            let toks: Vec<&str> = line.split_whitespace().collect();
+            let listening = toks.len() >= 5
+                && toks[0].eq_ignore_ascii_case("tcp")
+                && toks[1].ends_with(":47992")
+                && (toks[2] == "0.0.0.0:0" || toks[2] == "[::]:0");
+            let pid = *toks.last()?;
+            (listening && !pid.is_empty() && pid.bytes().all(|b| b.is_ascii_digit()))
+                .then(|| pid.to_string())
+        })
+        .collect()
+}
+
+/// Register the boot+logon/SYSTEM/restart-on-failure task via a generated Task Scheduler XML
+/// (`schtasks /xml`, no COM). The XML declares UTF-16, so it's written UTF-16LE+BOM.
+///
+/// Two triggers, because boot alone left too many holes: a console that lost the install-time start
+/// (or a box where the host service was started only later) had to wait for a full reboot. Logon is
+/// free insurance - `MultipleInstancesPolicy=IgnoreNew` makes a redundant start a no-op. If a
+/// Task Scheduler build rejects the two-trigger XML we fall back to the boot-only form rather than
+/// fail registration outright (no task at all is strictly worse than a boot-only task).
 fn register_web_task(cmd: &Path) -> Result<()> {
+    let cmd_xml = xml_escape(&cmd.to_string_lossy());
+    let boot = "<BootTrigger><Enabled>true</Enabled></BootTrigger>";
+    let boot_and_logon = "<BootTrigger><Enabled>true</Enabled></BootTrigger>\
+                          <LogonTrigger><Enabled>true</Enabled></LogonTrigger>";
+    if try_register_web_task(&cmd_xml, boot_and_logon) || try_register_web_task(&cmd_xml, boot) {
+        println!("registered scheduled task {WEB_TASK} -> {}", cmd.display());
+        Ok(())
+    } else {
+        bail!("schtasks /create {WEB_TASK} failed")
+    }
+}
+
+/// One `schtasks /create /xml` attempt with the given `<Triggers>` body. Returns whether it took.
+fn try_register_web_task(cmd_xml: &str, triggers: &str) -> bool {
     let xml = format!(
         "<?xml version=\"1.0\" encoding=\"UTF-16\"?>\n\
 <Task version=\"1.2\" xmlns=\"http://schemas.microsoft.com/windows/2004/02/mit/task\">\n\
   <RegistrationInfo><Description>punktfunk web management console (Nitro SSR on bun, :47992)</Description></RegistrationInfo>\n\
-  <Triggers><BootTrigger><Enabled>true</Enabled></BootTrigger></Triggers>\n\
+  <Triggers>{triggers}</Triggers>\n\
   <Principals><Principal id=\"Author\"><UserId>S-1-5-18</UserId><RunLevel>HighestAvailable</RunLevel></Principal></Principals>\n\
   <Settings>\n\
     <MultipleInstancesPolicy>IgnoreNew</MultipleInstancesPolicy>\n\
@@ -538,12 +618,13 @@ fn register_web_task(cmd: &Path) -> Result<()> {
     <ExecutionTimeLimit>PT0S</ExecutionTimeLimit>\n\
     <RestartOnFailure><Interval>PT1M</Interval><Count>10</Count></RestartOnFailure>\n\
   </Settings>\n\
-  <Actions Context=\"Author\"><Exec><Command>{}</Command></Exec></Actions>\n\
-</Task>",
-        xml_escape(&cmd.to_string_lossy())
+  <Actions Context=\"Author\"><Exec><Command>{cmd_xml}</Command></Exec></Actions>\n\
+</Task>"
     );
     let xml_path = std::env::temp_dir().join("punktfunk-web-task.xml");
-    write_utf16le_bom(&xml_path, &xml)?;
+    if write_utf16le_bom(&xml_path, &xml).is_err() {
+        return false;
+    }
     let ok = run_quiet(
         "schtasks",
         &[
@@ -556,12 +637,7 @@ fn register_web_task(cmd: &Path) -> Result<()> {
         ],
     );
     let _ = std::fs::remove_file(&xml_path);
-    if ok {
-        println!("registered scheduled task {WEB_TASK} -> {}", cmd.display());
-        Ok(())
-    } else {
-        bail!("schtasks /create {WEB_TASK} failed")
-    }
+    ok
 }
 
 fn write_utf16le_bom(path: &Path, s: &str) -> Result<()> {

docs-site/content/docs/gamescope.md

@@ -40,8 +40,16 @@ depends on the display manager driving the autologin:
 
 - **SDDM** (Bazzite, SteamOS): handled automatically — no setup.
 - **plasmalogin** (Nobara) and other display managers: the host must stop the display manager
-  itself for the length of the stream and restart it afterwards, which needs privilege. Allow it
-  with a polkit rule (adjust the unit and user names to your box):
+  itself for the length of the stream and restart it afterwards, which needs privilege. The
+  packages ship that privilege: a root helper (`/usr/libexec/punktfunk/pf-dm-helper`) behind its
+  own polkit action (`io.unom.punktfunk.dm-helper`), invoked automatically when the plain
+  `systemctl` verbs are denied — no setup. The helper only stops/restores the unit the
+  `display-manager.service` symlink points at, the same class of local-seat operation these
+  distros already authorize for their own session switcher (Nobara's `os-session-select`).
+
+  Installed from a tarball, or prefer not to ship the `allow_any` action? Remove the `.policy`
+  file and use a polkit rule scoped to your user instead (adjust the unit and user names to your
+  box) — the host tries the plain verbs first, so the rule takes precedence:
 
   ```js
   // /etc/polkit-1/rules.d/49-punktfunk-dm.rules
@@ -54,15 +62,16 @@ depends on the display manager driving the autologin:
   });
   ```
 
-  Without the rule the host degrades safely: it **attaches** to the live Gaming Mode session
-  instead (Game Mode stays on the box's display, mirrored to the client) rather than risk the
-  display manager. If the display-manager restart ever loses its privilege mid-restore,
-  `PUNKTFUNK_RECOVER_SESSION_CMD` (see [Configuration](/docs/configuration)) is fired as the
-  fallback.
+  With no privilege path at all the host degrades safely: it **attaches** to the live Gaming Mode
+  session instead (Game Mode stays on the box's display at the box's own resolution, mirrored to
+  the client — if your monitor stays on and the stream runs at the desktop's resolution, this is
+  what happened; check the host log for "managed takeover unavailable"). If the display-manager
+  restart ever loses its privilege mid-restore, `PUNKTFUNK_RECOVER_SESSION_CMD` (see
+  [Configuration](/docs/configuration)) is fired as the fallback.
 
-  With the rule in place the **in-stream session switch round-trips** in managed mode: Steam's
-  "Switch to Desktop" inside the streamed Game Mode returns the box to its desktop session and the
-  stream follows it there; the desktop's "Return to Gaming Mode" switches it forward again.
+  With the takeover authorized the **in-stream session switch round-trips** in managed mode:
+  Steam's "Switch to Desktop" inside the streamed Game Mode returns the box to its desktop session
+  and the stream follows it there; the desktop's "Return to Gaming Mode" switches it forward again.
 
 ## Session following
 

docs-site/content/docs/windows-host.md

@@ -66,7 +66,7 @@ the Windows specifics follow.
 
 The installer also sets up the **web management console** (status, paired devices, the PIN pairing
 flow): it bundles the console plus its own runtime and runs it as the **`PunktfunkWeb`** task on
-**`https://<this-PC>:47992`**, starting at boot.
+**`https://<this-PC>:47992`**, starting at boot and at sign-in.
 
 #### Console login password
 

packaging/arch/PKGBUILD

@@ -129,6 +129,14 @@ package_punktfunk-host() {
   install -Dm0755 "$T/punktfunk-host"                 "$pkgdir/usr/bin/punktfunk-host"
   # /dev/uinput + /dev/uhid -> input group (virtual gamepads + DualSense UHID)
   install -Dm0644 "$R/scripts/60-punktfunk.rules"     "$pkgdir/usr/lib/udev/rules.d/60-punktfunk.rules"
+  # Managed gamescope takeover on DM-autologin boxes: root helper + polkit action so the host can
+  # stop/restore the display manager for the stream. Arch has no /usr/libexec — install under
+  # /usr/lib/punktfunk and rewrite the policy's exec.path annotation to match (the host probes both).
+  install -Dm0755 "$R/scripts/pf-dm-helper"           "$pkgdir/usr/lib/punktfunk/pf-dm-helper"
+  install -Dm0644 "$R/scripts/io.unom.punktfunk.dm-helper.policy" \
+    "$pkgdir/usr/share/polkit-1/actions/io.unom.punktfunk.dm-helper.policy"
+  sed -i 's#/usr/libexec/punktfunk/pf-dm-helper#/usr/lib/punktfunk/pf-dm-helper#' \
+    "$pkgdir/usr/share/polkit-1/actions/io.unom.punktfunk.dm-helper.policy"
   # vhci-hcd autoload — usbip transport for the virtual Steam Deck pad (Steam only adopts USB pads)
   install -Dm0644 "$R/scripts/punktfunk-modules.conf" "$pkgdir/usr/lib/modules-load.d/punktfunk.conf"
   # 32 MB UDP socket buffers (send-side headroom at high bitrate)

packaging/debian/build-deb.sh

@@ -52,6 +52,11 @@ SHAREDIR="$STAGE/usr/share/$PKG"
 # --- file layout (matches the RPM %install) ----------------------------------
 install -Dm0755 "$BIN"                              "$STAGE/usr/bin/$PKG"
 install -Dm0644 scripts/60-punktfunk.rules         "$STAGE/usr/lib/udev/rules.d/60-punktfunk.rules"
+# Managed gamescope takeover on DM-autologin boxes: root helper + polkit action so the host can
+# stop/restore the display manager for the stream (the helper derives the DM unit itself).
+install -Dm0755 scripts/pf-dm-helper               "$STAGE/usr/libexec/punktfunk/pf-dm-helper"
+install -Dm0644 scripts/io.unom.punktfunk.dm-helper.policy \
+                                                   "$STAGE/usr/share/polkit-1/actions/io.unom.punktfunk.dm-helper.policy"
 # vhci-hcd autoload — usbip transport for the virtual Steam Deck pad (Steam only adopts USB pads).
 install -Dm0644 scripts/punktfunk-modules.conf     "$STAGE/usr/lib/modules-load.d/punktfunk.conf"
 # UDP socket-buffer tuning (32 MB) — without it the kernel clamps the host's SO_SNDBUF to ~416 KB

packaging/rpm/punktfunk.spec

@@ -249,6 +249,12 @@ install -Dm0755 target/release/punktfunk-host %{buildroot}%{_bindir}/punktfunk-h
 # udev rule — /dev/uinput access for virtual gamepads (input group).
 install -Dm0644 scripts/60-punktfunk.rules %{buildroot}%{_udevrulesdir}/60-punktfunk.rules
 
+# Managed gamescope takeover on DM-autologin boxes (Nobara's plasmalogin): a root helper + polkit
+# action let the host stop/restore the display manager for the stream without a hand-installed
+# polkit rule. The helper derives the DM unit itself — callers can't name arbitrary units.
+install -Dm0755 scripts/pf-dm-helper %{buildroot}%{_libexecdir}/punktfunk/pf-dm-helper
+install -Dm0644 scripts/io.unom.punktfunk.dm-helper.policy %{buildroot}%{_datadir}/polkit-1/actions/io.unom.punktfunk.dm-helper.policy
+
 # vhci-hcd autoload — the usbip transport that makes the virtual Steam Deck controller a
 # real USB device (Steam Input only adopts those; the UHID fallback is invisible to Steam).
 install -Dm0644 scripts/punktfunk-modules.conf %{buildroot}%{_prefix}/lib/modules-load.d/punktfunk.conf
@@ -383,6 +389,9 @@ install -Dm0644 scripts/punktfunk-scripting.service %{buildroot}%{_userunitdir}/
 %{_bindir}/punktfunk-host
 %{_bindir}/punktfunk-tray
 %{_udevrulesdir}/60-punktfunk.rules
+%dir %{_libexecdir}/punktfunk
+%{_libexecdir}/punktfunk/pf-dm-helper
+%{_datadir}/polkit-1/actions/io.unom.punktfunk.dm-helper.policy
 %{_prefix}/lib/modules-load.d/punktfunk.conf
 %{_prefix}/lib/sysctl.d/99-punktfunk-net.conf
 %{_prefix}/lib/firewalld/services/punktfunk-gamestream.xml

scripts/io.unom.punktfunk.dm-helper.policy

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE policyconfig PUBLIC
+ "-//freedesktop//DTD PolicyKit Policy Configuration 1.0//EN"
+ "http://www.freedesktop.org/standards/PolicyKit/1.0/policyconfig.dtd">
+<policyconfig>
+  <vendor>Punktfunk</vendor>
+  <vendor_url>https://punktfunk.unom.io</vendor_url>
+
+  <!-- Stop/restore the box's display manager for a managed gamescope takeover. The helper derives
+       the unit from the display-manager.service symlink itself (no caller-chosen units), so this
+       grant is scoped to the box's own local-seat session lifecycle — the same class of operation
+       these distros already authorize for their session switcher (e.g. Nobara's
+       os-session-select, allow_any). allow_any because the host commonly runs sessionless (a
+       lingering user unit, no polkit agent), where interactive auth can never be answered. -->
+  <action id="io.unom.punktfunk.dm-helper">
+    <description>Stop or restore the display manager for a Punktfunk stream</description>
+    <message>Authentication is required to switch the display manager for a Punktfunk stream</message>
+    <defaults>
+      <allow_any>yes</allow_any>
+      <allow_inactive>yes</allow_inactive>
+      <allow_active>yes</allow_active>
+    </defaults>
+    <annotate key="org.freedesktop.policykit.exec.path">/usr/libexec/punktfunk/pf-dm-helper</annotate>
+  </action>
+</policyconfig>

scripts/pf-dm-helper

@@ -0,0 +1,39 @@
+#!/bin/sh
+# Privileged display-manager verbs for the punktfunk managed gamescope takeover.
+#
+# On DM-autologin boxes whose display manager does not survive a masked session unit (Nobara's
+# plasmalogin, unknown DMs), taking the Gaming Mode session over means stopping the display
+# manager for the length of the stream and restarting it afterwards — root-only operations. The
+# host invokes this helper via pkexec under its own polkit action
+# (io.unom.punktfunk.dm-helper.policy, installed by the packages), the same mechanism these
+# distros use for their own session switching (Nobara's os-session-select).
+#
+# The unit is NEVER caller-controlled: it is derived here from the display-manager.service alias
+# symlink, so the polkit grant's blast radius is exactly "the box's own display manager" — a
+# local-seat operation, not arbitrary unit management.
+set -eu
+
+dm_unit() {
+  target=$(readlink /etc/systemd/system/display-manager.service) || {
+    echo "pf-dm-helper: no display-manager.service alias — no display manager to manage" >&2
+    exit 1
+  }
+  basename "$target"
+}
+
+case "${1-}" in
+  stop)
+    exec systemctl stop "$(dm_unit)"
+    ;;
+  restore)
+    dm=$(dm_unit)
+    # reset-failed first: a relogin loop may have tripped the unit's start limit, and a plain
+    # restart would be refused until the accounting is cleared.
+    systemctl reset-failed "$dm" 2>/dev/null || :
+    exec systemctl restart "$dm"
+    ;;
+  *)
+    echo "usage: pf-dm-helper stop|restore" >&2
+    exit 2
+    ;;
+esac

scripts/punktfunk-web.service

@@ -12,6 +12,11 @@ Description=punktfunk management web console
 # web-init generates the login password; the host writes the mgmt token. Order after both.
 After=punktfunk-web-init.service punktfunk-host.service
 Wants=punktfunk-web-init.service
+# Retry indefinitely while the host is still writing the mgmt token + identity cert. Without this,
+# systemd's default rate limit (5 starts / 10 s) plus RestartSec=2 gives up permanently after ~10 s
+# - so a console enabled before the host's first run stayed dead until someone restarted it by hand
+# (the same defect the Windows PunktfunkWeb task had).
+StartLimitIntervalSec=0
 
 [Service]
 Type=simple

scripts/windows/web-run.cmd

@@ -16,17 +16,26 @@ set "CERTFILE=%PFDATA%\cert.pem"
 set "KEYFILE=%PFDATA%\key.pem"
 
 rem The host's `serve` writes the mgmt token + its identity cert/key on first run. Until they exist
-rem we have no credential and no TLS material, so fail and let the task's restart-on-failure retry
-rem (mirrors the Linux unit's Restart=on-failure waiting for the host to create them) rather than
-rem silently downgrading to plain HTTP.
-if not exist "%TOKENFILE%" (
-  echo [punktfunk-web] mgmt token not present yet at "%TOKENFILE%" - waiting for the host service.
-  exit /b 1
-)
-if not exist "%CERTFILE%" (
-  echo [punktfunk-web] host identity cert not present yet at "%CERTFILE%" - waiting for the host service.
+rem we have no credential and no TLS material, so WAIT rather than silently downgrading to plain HTTP.
+rem
+rem Wait in-process instead of exiting 1 and hoping the task's restart-on-failure retries: Task
+rem Scheduler does not reliably restart on a plain non-zero exit code, so a console that started
+rem before the host finished writing those files (the token lands at argument parse, the cert only
+rem after the RSA-2048 keygen) used to stay down until the next reboot. ~5 min at 2 s, then give up
+rem so a genuinely broken install still surfaces as a failed task rather than one that runs forever.
+rem `timeout` needs a console this task does not have, so `ping -n 3` is the 2-second sleep.
+set /a PFWAITS=0
+:pfwait
+if exist "%TOKENFILE%" if exist "%CERTFILE%" goto pfready
+if %PFWAITS% GEQ 150 (
+  echo [punktfunk-web] gave up waiting for "%TOKENFILE%" + "%CERTFILE%" - is the punktfunk host service running?
   exit /b 1
 )
+if %PFWAITS%==0 echo [punktfunk-web] waiting for the host service to write the mgmt token + identity cert...
+set /a PFWAITS+=1
+ping -n 3 127.0.0.1 >nul 2>&1
+goto pfwait
+:pfready
 
 rem Both files are single KEY=VALUE lines (LF), written 0600/ACL'd: PUNKTFUNK_MGMT_TOKEN=... and
 rem PUNKTFUNK_UI_PASSWORD=... . Split on the first '=' and import each into the environment.

web/web-run.cmd

@@ -18,16 +18,21 @@ set "CERTFILE=%PFDATA%\cert.pem"
 set "KEYFILE=%PFDATA%\key.pem"
 
 rem The host's `serve` writes the mgmt token + identity cert on first run. Until they exist the proxy
-rem has no credential and no TLS material, so fail and let restart-on-failure retry (mirrors the
-rem installed launcher / Linux unit) rather than silently serving plain HTTP.
-if not exist "%TOKENFILE%" (
-  echo [punktfunk-web] mgmt token not present yet at "%TOKENFILE%" - waiting for the host service.
-  exit /b 1
-)
-if not exist "%CERTFILE%" (
-  echo [punktfunk-web] host identity cert not present yet at "%CERTFILE%" - waiting for the host service.
+rem has no credential and no TLS material, so WAIT for them (mirrors the installed launcher) rather
+rem than silently serving plain HTTP - see scripts\windows\web-run.cmd for why waiting here beats
+rem exiting 1 and relying on the task's restart-on-failure. ~5 min at 2 s, then give up.
+set /a PFWAITS=0
+:pfwait
+if exist "%TOKENFILE%" if exist "%CERTFILE%" goto pfready
+if %PFWAITS% GEQ 150 (
+  echo [punktfunk-web] gave up waiting for "%TOKENFILE%" + "%CERTFILE%" - is the punktfunk host running?
   exit /b 1
 )
+if %PFWAITS%==0 echo [punktfunk-web] waiting for the host to write the mgmt token + identity cert...
+set /a PFWAITS+=1
+ping -n 3 127.0.0.1 >nul 2>&1
+goto pfwait
+:pfready
 
 rem Both files are single KEY=VALUE lines: PUNKTFUNK_MGMT_TOKEN=... and PUNKTFUNK_UI_PASSWORD=... .
 rem Split on the first '=' and import each into the environment.