fix(slint): network-folder visibility keyed on connectivity, playback lock on missing files

Root cause of the empty Albums tab: transposed positional booleans from
the Plex-port rewrite (a45840d1) left exclude_network_folders=true and
include_qobuz_downloads=false unconditionally on every browse query since
2026-06-07. The owner-approved model replaces it: network-folder content
hides ONLY under hard offline (link confirmed down - no link means no LAN
mounts either); a logged-out session or induced offline with the link up
shows everything (the Qobuz verdict says nothing about NFS/SMB). The
show-network-folders toggle is retired from Settings (DB column stays,
Tauri-compatible).

Playback lock instead of hiding: local tracks get an existence check at
the play seam and in the advance walk (FileMissing verdict, 'is the drive
mounted?' toasts, never on the audio thread - D-state caveat documented).

Scan-cleanup guard: tracks under a network folder whose mount is
unreachable are never treated as missing (a refresh pressed before
remounting used to hard-delete the folder's whole index). mount_info: nfs4
and smb3-style version suffixes now classify as network (its red test is
green) and the longest-mount match respects path boundaries.

cc

crates/qbz-library/src/mount_info.rs

@@ -56,22 +56,9 @@ pub fn is_network_path(path: &Path) -> bool {
     let target = path
         .canonicalize()
         .unwrap_or_else(|_| path.to_path_buf());
-    let target_str = target.to_string_lossy();
 
-    // Longest-prefix match wins — `/` is always present but any
-    // deeper mount shadows it.
-    let mut best: Option<(&str, usize)> = None;
-    for (mount_point, fs_type) in &mounts {
-        if target_str.starts_with(mount_point) {
-            let len = mount_point.len();
-            if best.map(|(_, l)| l < len).unwrap_or(true) {
-                best = Some((fs_type.as_str(), len));
-            }
-        }
-    }
-
-    match best {
-        Some((fs_type, _)) => is_network_fs(fs_type),
+    match best_fs_type(&mounts, &target.to_string_lossy()) {
+        Some(fs_type) => is_network_fs(fs_type),
         None => false,
     }
 }
@@ -96,24 +83,48 @@ pub fn network_fs_label(path: &Path) -> Option<String> {
     let target = path
         .canonicalize()
         .unwrap_or_else(|_| path.to_path_buf());
-    let target_str = target.to_string_lossy();
 
-    let mut best: Option<(&str, usize)> = None;
-    for (mount_point, fs_type) in &mounts {
-        if target_str.starts_with(mount_point) {
-            let len = mount_point.len();
-            if best.map(|(_, l)| l < len).unwrap_or(true) {
-                best = Some((fs_type.as_str(), len));
-            }
-        }
-    }
-    let fs_type = best.map(|(t, _)| t)?;
+    let fs_type = best_fs_type(&mounts, &target.to_string_lossy())?;
     if !is_network_fs(fs_type) {
         return None;
     }
     Some(normalize_network_label(fs_type))
 }
 
+/// Longest-mount-point match of `target` against the mount table, honoring
+/// path-component boundaries: `/mnt/music` matches `/mnt/music` and
+/// `/mnt/music/Albums/x.flac` but NOT `/mnt/music2` (the previous raw
+/// `starts_with` matched the sibling too, inheriting the wrong fs type).
+/// `/` is always present and any deeper mount shadows it.
+#[cfg(target_os = "linux")]
+fn best_fs_type<'a>(mounts: &'a [(String, String)], target: &str) -> Option<&'a str> {
+    let mut best: Option<(&'a str, usize)> = None;
+    for (mount_point, fs_type) in mounts {
+        if !path_within_mount(target, mount_point) {
+            continue;
+        }
+        let len = mount_point.len();
+        if best.map(|(_, l)| l < len).unwrap_or(true) {
+            best = Some((fs_type.as_str(), len));
+        }
+    }
+    best.map(|(t, _)| t)
+}
+
+/// True when `target` IS `mount_point` or lives underneath it, on a path
+/// component boundary.
+#[cfg(target_os = "linux")]
+fn path_within_mount(target: &str, mount_point: &str) -> bool {
+    if mount_point == "/" {
+        return target.starts_with('/');
+    }
+    match target.strip_prefix(mount_point.trim_end_matches('/')) {
+        Some("") => true,
+        Some(rest) => rest.starts_with('/'),
+        None => false,
+    }
+}
+
 #[cfg(not(target_os = "linux"))]
 pub fn network_fs_label(_path: &Path) -> Option<String> {
     None
@@ -180,9 +191,20 @@ fn parse_mounts(contents: &str) -> Vec<(String, String)> {
 
 #[cfg(target_os = "linux")]
 fn is_network_fs(fs_type: &str) -> bool {
+    // A prefix hits on: the exact type ("nfs", "cifs"), a dotted scheme
+    // ("fuse.sshfs.x"), or a version suffix ("nfs4", "nfs3", "smb3" — pure
+    // digits after the prefix). The previous `== || starts_with("{prefix}.")`
+    // missed the version-suffixed forms, so `nfs4` — the fs type every
+    // modern NFS mount reports in /proc/mounts — classified as LOCAL.
     NETWORK_FS_PREFIXES
         .iter()
-        .any(|prefix| fs_type == *prefix || fs_type.starts_with(&format!("{}.", prefix)))
+        .any(|prefix| match fs_type.strip_prefix(prefix) {
+            Some("") => true,
+            Some(rest) => {
+                rest.starts_with('.') || rest.chars().all(|c| c.is_ascii_digit())
+            }
+            None => false,
+        })
 }
 
 #[cfg(all(test, target_os = "linux"))]
@@ -207,6 +229,31 @@ mod tests {
         assert!(!is_network_fs("fuse.gocryptfs"));
     }
 
+    #[test]
+    fn best_fs_type_respects_path_boundaries() {
+        let mounts = vec![
+            ("/".to_string(), "ext4".to_string()),
+            ("/mnt/music".to_string(), "nfs4".to_string()),
+        ];
+        assert_eq!(best_fs_type(&mounts, "/mnt/music"), Some("nfs4"));
+        assert_eq!(best_fs_type(&mounts, "/mnt/music/Albums/x.flac"), Some("nfs4"));
+        // A sibling dir sharing the string prefix must NOT inherit the
+        // mount's fs type — it falls through to `/`.
+        assert_eq!(best_fs_type(&mounts, "/mnt/music2/x.flac"), Some("ext4"));
+    }
+
+    #[test]
+    fn best_fs_type_longest_mount_wins() {
+        let mounts = vec![
+            ("/".to_string(), "ext4".to_string()),
+            ("/mnt".to_string(), "xfs".to_string()),
+            ("/mnt/nas".to_string(), "cifs".to_string()),
+        ];
+        assert_eq!(best_fs_type(&mounts, "/mnt/nas/music"), Some("cifs"));
+        assert_eq!(best_fs_type(&mounts, "/mnt/local"), Some("xfs"));
+        assert_eq!(best_fs_type(&mounts, "/home/user"), Some("ext4"));
+    }
+
     #[test]
     fn parse_mounts_reads_typical_entries() {
         let sample = "\

crates/qbz-library/src/scan.rs

@@ -316,30 +316,49 @@ pub fn scan_with_progress(
 
     // Cleanup: remove tracks whose files no longer exist. Full scan checks the
     // whole DB; single-folder scan only the scanned folders' subtrees.
+    //
+    // GUARD: a network folder whose mount is currently DOWN must not have its
+    // subtree treated as missing — while unmounted every stat fails, and
+    // deleting the rows would wipe a whole folder's index over a transient
+    // condition (e.g. a reboot where the share didn't auto-mount). Those
+    // subtrees are skipped; they rehabilitate on the next scan after remount.
     on_event(ScanEvent::Cleanup);
+    let folder_prefix = |path: &str| {
+        if path.ends_with('/') {
+            path.to_string()
+        } else {
+            format!("{}/", path)
+        }
+    };
+    let unavailable_prefixes: Vec<String> = db
+        .get_folders_with_metadata()
+        .map(|folders| {
+            folders
+                .iter()
+                .filter(|f| f.is_network && std::fs::read_dir(&f.path).is_err())
+                .map(|f| folder_prefix(&f.path))
+                .collect()
+        })
+        .unwrap_or_default();
+    let under_unavailable =
+        |p: &str| unavailable_prefixes.iter().any(|pre| p.starts_with(pre.as_str()));
     if let Ok(tracks) = db.get_all_track_paths() {
         let missing: Vec<i64> = if single {
-            let prefixes: Vec<String> = targets
-                .iter()
-                .map(|f| {
-                    if f.path.ends_with('/') {
-                        f.path.clone()
-                    } else {
-                        format!("{}/", f.path)
-                    }
-                })
-                .collect();
+            let prefixes: Vec<String> =
+                targets.iter().map(|f| folder_prefix(&f.path)).collect();
             tracks
                 .iter()
                 .filter(|(_, p)| {
-                    prefixes.iter().any(|pre| p.starts_with(pre)) && !Path::new(p).exists()
+                    prefixes.iter().any(|pre| p.starts_with(pre))
+                        && !under_unavailable(p)
+                        && !Path::new(p).exists()
                 })
                 .map(|(id, _)| *id)
                 .collect()
         } else {
             tracks
                 .iter()
-                .filter(|(_, p)| !Path::new(p).exists())
+                .filter(|(_, p)| !under_unavailable(p) && !Path::new(p).exists())
                 .map(|(id, _)| *id)
                 .collect()
         };

crates/qbz-slint/src/local_library.rs

@@ -459,6 +459,42 @@ fn plex_cache_db_path() -> Option<std::path::PathBuf> {
     dirs::data_dir().map(|d| d.join("qbz").join("plex_cache.db"))
 }
 
+// NETWORK-FOLDER VISIBILITY (owner verdict 2026-06-10, refined same day):
+// hiding network-folder content is keyed on RAW CONNECTIVITY, never on the
+// offline MODE. A logged-out session or induced offline with the link up
+// says nothing about LAN mounts — content stays visible there (offline mode
+// exists precisely to use the local library). Only a CONFIRMED-down link
+// (hard offline: no default route / probes dead) hides network folders, the
+// one state where LAN mounts are gone too. An unmounted-while-online path is
+// handled at PLAYBACK time instead (existence guard + friendly toast in
+// playback.rs), not by hiding library content.
+//
+// Known approximation, accepted with the model: an ISP outage with a live
+// LAN reads as hard offline and hides NAS content; per-mount accessibility
+// checks in every browse query would be the exact-but-costly alternative.
+
+/// True only under HARD offline (connectivity confirmed down). See the
+/// NETWORK-FOLDER VISIBILITY note above.
+pub(crate) fn exclude_network_folders_now() -> bool {
+    crate::offline_mode::engine().status().connectivity
+        == qbz_app::offline_mode::Connectivity::Down
+}
+
+/// Reset the four browse-tab models so each tab re-fetches on its next visit
+/// (the `ensure_*_loaded` guards key on an empty model). Used after a scan,
+/// after the danger-zone clear, and on offline-mode flips (where the
+/// connectivity-keyed network-folder gate may change the browse SET — see
+/// the NETWORK-FOLDER VISIBILITY note above).
+pub fn reset_browse_models(window: &AppWindow) {
+    let s = window.global::<LocalLibraryState>();
+    let empty_albums = ModelRc::new(VecModel::from(Vec::<AlbumCardItem>::new()));
+    let empty_tracks = ModelRc::new(VecModel::from(Vec::<TrackItem>::new()));
+    s.set_albums(empty_albums.clone());
+    s.set_folders(empty_albums);
+    s.set_tracks(empty_tracks);
+    s.set_artists(ModelRc::new(VecModel::from(Vec::<LocalArtistItem>::new())));
+}
+
 /// Upper bound for the full-load page. The Albums tab loads the entire set in
 /// one shot (search/sort/filter/group are all derived client-side over the
 /// cached set in `derive_albums`), so we request a single large page rather
@@ -485,6 +521,11 @@ fn spawn_albums_load(
     handle.spawn(async move {
         let loaded: Option<(Vec<qbz_library::LocalAlbum>, Vec<crate::album_map::AlbumCard>)> =
             tokio::task::spawn_blocking(move || {
+                // include_qobuz_downloads: true (offline copies belong in the
+                // grid — the toolbar's "Offline" source filter selects them).
+                // exclude_network_folders: connectivity-keyed — see the
+                // NETWORK-FOLDER VISIBILITY note.
+                let exclude_network = exclude_network_folders_now();
                 crate::library_db::with_db(|db| {
                     let page = db.get_albums_metadata_page(
                         0,
@@ -492,8 +533,8 @@ fn spawn_albums_load(
                         None,
                         "artist",
                         "asc",
-                        false,
                         true,
+                        exclude_network,
                         plex_path.as_deref(),
                     )?;
                     let albums = page.albums;
@@ -581,6 +622,10 @@ pub fn seed_counts(weak: slint::Weak<AppWindow>, handle: tokio::runtime::Handle)
     let plex_enabled = crate::plex_settings::get().enabled;
     handle.spawn(async move {
         let counts: Option<(usize, usize, usize, usize)> = tokio::task::spawn_blocking(move || {
+            // Same include-qobuz / network flags as the Albums tab loader, so
+            // the badge always matches the grid (network content always in —
+            // see the NETWORK-FOLDER VISIBILITY note).
+            let exclude_network = exclude_network_folders_now();
             crate::library_db::with_db(|db| {
                 // Total under the same filter the Albums tab uses, incl. the
                 // Plex union when enabled, so the badge matches the grid.
@@ -591,8 +636,8 @@ pub fn seed_counts(weak: slint::Weak<AppWindow>, handle: tokio::runtime::Handle)
                         None,
                         "artist",
                         "asc",
-                        false,
                         true,
+                        exclude_network,
                         plex_path.as_deref(),
                     )
                     .map(|p| p.total as usize)
@@ -759,8 +804,11 @@ fn fetch_tracks_page(
     offset: u64,
     plex: bool,
 ) -> Option<(Vec<qbz_library::LocalTrack>, bool)> {
+    // exclude_network_folders: connectivity-keyed — see the NETWORK-FOLDER
+    // VISIBILITY note.
+    let exclude_network = exclude_network_folders_now();
     let mut rows = crate::library_db::with_db(|db| {
-        db.search_with_filter_page(query.trim(), offset, TRACKS_PAGE, true, false)
+        db.search_with_filter_page(query.trim(), offset, TRACKS_PAGE, true, exclude_network)
     })?;
     let has_more = rows.len() as u64 == TRACKS_PAGE;
     if plex && offset == 0 {
@@ -1401,6 +1449,10 @@ fn spawn_plex_quality_hydration(
             // The album aggregate (MAX over tracks) is a pure runtime query; the
             // refreshed Plex track quality flows into it automatically.
             let album = plex_path.as_deref().and_then(|p| {
+                // Same flags as the Albums tab loader so the looked-up
+                // aggregate comes from the identical set (network content
+                // always in — see the NETWORK-FOLDER VISIBILITY note).
+                let exclude_network = exclude_network_folders_now();
                 crate::library_db::with_db(|db| {
                     let page = db.get_albums_metadata_page(
                         0,
@@ -1408,8 +1460,8 @@ fn spawn_plex_quality_hydration(
                         None,
                         "artist",
                         "asc",
-                        false,
                         true,
+                        exclude_network,
                         Some(p),
                     )?;
                     Ok(page.albums.into_iter().find(|a| a.id == gk))
@@ -1631,11 +1683,15 @@ pub fn current_album_version_tracks(window: &AppWindow) -> Vec<qbz_library::Loca
 // the Tracks table). Reuses AlbumCollectionView; covers load per card.
 
 fn fetch_folder_albums() -> Vec<crate::album_map::AlbumCard> {
-    crate::library_db::with_db(|db| {
+    // exclude_network_folders: connectivity-keyed — an unmounted-but-online
+    // folder stays visible (the index is the source); only hard offline
+    // hides it (see the NETWORK-FOLDER VISIBILITY note).
+    let exclude_network = exclude_network_folders_now();
+    crate::library_db::with_db(move |db| {
         db.get_albums_with_full_filter(
             /* include_hidden */ false,
             /* include_qobuz_downloads */ true,
-            /* exclude_network_folders */ false,
+            exclude_network,
         )
     })
     .unwrap_or_default()
@@ -2792,8 +2848,13 @@ pub fn ensure_artists_loaded(
         let plex_path = plex_cache_db_path();
         handle.spawn(async move {
             let items = tokio::task::spawn_blocking(move || {
-                let artists = crate::library_db::with_db(|db| db.get_artists_with_filter(true, false))
-                    .unwrap_or_default();
+                // Same network flag as every browse tab: connectivity-keyed
+                // — see the NETWORK-FOLDER VISIBILITY note.
+                let exclude_network = exclude_network_folders_now();
+                let artists = crate::library_db::with_db(|db| {
+                    db.get_artists_with_filter(true, exclude_network)
+                })
+                .unwrap_or_default();
                 // Album cache for the right pane + album_count. With Plex ON,
                 // use the Plex-aware ATTACH/union query so the artist-detail grid
                 // and counts include Plex albums (1:1 with the Albums tab set);
@@ -2806,8 +2867,8 @@ pub fn ensure_artists_loaded(
                             None,
                             "artist",
                             "asc",
-                            false,
                             true,
+                            exclude_network,
                             plex_path.as_deref(),
                         )
                         .map(|p| p.albums)
@@ -2815,7 +2876,7 @@ pub fn ensure_artists_loaded(
                     .unwrap_or_default()
                 } else {
                     crate::library_db::with_db(|db| {
-                        db.get_albums_with_full_filter(false, true, false)
+                        db.get_albums_with_full_filter(false, true, exclude_network)
                     })
                     .unwrap_or_default()
                 };

crates/qbz-slint/src/local_library_settings.rs

@@ -515,10 +515,31 @@ pub fn cleanup_missing(weak: Weak<AppWindow>, handle: tokio::runtime::Handle) {
     handle.spawn(async move {
         let result = tokio::task::spawn_blocking(|| {
             let paths = crate::library_db::with_db(|db| db.get_all_track_paths())?;
+            // Same guard as the scan's cleanup phase: a network folder whose
+            // mount is DOWN right now stats as missing for every file — that
+            // is "unreachable", not "deleted". Skip those subtrees so a
+            // maintenance click while a share is unmounted can't wipe its
+            // index.
+            let skip: Vec<String> =
+                crate::library_db::with_db(|db| db.get_folders_with_metadata())
+                    .unwrap_or_default()
+                    .into_iter()
+                    .filter(|f| f.is_network && std::fs::read_dir(&f.path).is_err())
+                    .map(|f| {
+                        if f.path.ends_with('/') {
+                            f.path
+                        } else {
+                            format!("{}/", f.path)
+                        }
+                    })
+                    .collect();
             let checked = paths.len();
             let missing: Vec<i64> = paths
                 .into_iter()
-                .filter(|(_, p)| !std::path::Path::new(p).exists())
+                .filter(|(_, p)| {
+                    !skip.iter().any(|pre| p.starts_with(pre.as_str()))
+                        && !std::path::Path::new(p).exists()
+                })
                 .map(|(id, _)| id)
                 .collect();
             let mut removed = 0usize;
@@ -602,13 +623,7 @@ pub fn clear_library(weak: Weak<AppWindow>, handle: tokio::runtime::Handle) {
         let _ = weak.upgrade_in_event_loop(|w| {
             w.global::<LibraryFoldersState>().set_clearing_library(false);
             // Reset the browse models so the tabs re-fetch on next visit.
-            let s = w.global::<crate::LocalLibraryState>();
-            let empty_albums = ModelRc::new(VecModel::from(Vec::<crate::AlbumCardItem>::new()));
-            let empty_tracks = ModelRc::new(VecModel::from(Vec::<crate::TrackItem>::new()));
-            s.set_albums(empty_albums.clone());
-            s.set_folders(empty_albums);
-            s.set_tracks(empty_tracks);
-            s.set_artists(ModelRc::new(VecModel::from(Vec::<crate::LocalArtistItem>::new())));
+            crate::local_library::reset_browse_models(&w);
         });
         if ok {
             crate::toast::success_weak(&weak, "Library database cleared");
@@ -752,13 +767,7 @@ fn run_scan(weak: Weak<AppWindow>, handle: tokio::runtime::Handle, ids: Option<V
         // Post-scan: refresh the folder list (last_scan labels) + reset the
         // browse models so the tabs re-fetch the new index on next visit.
         let _ = weak.upgrade_in_event_loop(|w| {
-            let s = w.global::<crate::LocalLibraryState>();
-            let empty_albums = ModelRc::new(VecModel::from(Vec::<crate::AlbumCardItem>::new()));
-            let empty_tracks = ModelRc::new(VecModel::from(Vec::<crate::TrackItem>::new()));
-            s.set_albums(empty_albums.clone());
-            s.set_folders(empty_albums);
-            s.set_tracks(empty_tracks);
-            s.set_artists(ModelRc::new(VecModel::from(Vec::<crate::LocalArtistItem>::new())));
+            crate::local_library::reset_browse_models(&w);
         });
         load_folders(weak, h);
     });

crates/qbz-slint/src/myqbz_builder.rs

@@ -415,15 +415,20 @@ pub fn fetch_local_and_plex(artist_name: &str) -> Vec<Candidate> {
     // local rows carry `a.artwork_path`, with the same cover.jpg/folder.jpg
     // on-disk fallback the grid uses so a DB row missing artwork_path still
     // resolves a cover.
-    crate::library_db::with_db(|db| {
+    // Same flags as the LocalLibrary Albums tab (include offline copies;
+    // network content connectivity-keyed — see local_library.rs's
+    // NETWORK-FOLDER VISIBILITY note) so the builder sees the identical
+    // candidate set.
+    let exclude_network = crate::local_library::exclude_network_folders_now();
+    crate::library_db::with_db(move |db| {
         let page = db.get_albums_metadata_page(
             0,
             1_000_000,
             None,
             "artist",
             "asc",
-            false,
             true,
+            exclude_network,
             plex_path.as_deref(),
         )?;
         let out: Vec<Candidate> = page

crates/qbz-slint/src/playback.rs

@@ -221,18 +221,60 @@ enum OfflinePlayability {
     /// The track IS offline-cached but the D4 subscription grace window has
     /// elapsed — gets its own honest message.
     GraceExpired,
+    /// A LOCAL user file whose indexed path is not on disk right now —
+    /// typically an unmounted network drive. Checked online AND offline
+    /// (library content is never hidden, so playback is where this must
+    /// surface) — gets the "is the drive mounted?" message.
+    FileMissing,
+}
+
+/// Cheap existence guard for a LOCAL queue track's underlying file: resolve
+/// the indexed path (ephemeral store, or one indexed library-DB read) and
+/// stat it with `Path::exists()`. Unresolvable id/path → `true` (don't
+/// invent a skip; the play path has its own not-found handling).
+///
+/// D-STATE CAVEAT: `exists()` on an UNMOUNTED path returns false instantly
+/// (the path simply isn't there) — that is the case this guards. But a stat
+/// on a DEAD-yet-still-MOUNTED NFS/CIFS share can block in uninterruptible
+/// sleep (D state). This is therefore only ever called from the async layer
+/// (the advance walk and the play fast-fail run on the tokio runtime;
+/// `play_local_file_audible` checks inside `spawn_blocking`) and NEVER from
+/// the audio callback thread — a worst-case hang stalls an advance, not the
+/// audio pipeline. Do NOT add mount probing here; the hot path stays one
+/// stat per advance.
+fn local_track_file_exists(track: &QueueTrack) -> bool {
+    let path = if crate::ephemeral::is_ephemeral_id(track.id as i64) {
+        crate::ephemeral::get_track(track.id as i64).map(|row| row.file_path)
+    } else {
+        crate::library_db::with_db(|db| db.get_track(track.id as i64))
+            .flatten()
+            .map(|row| row.file_path)
+    };
+    match path {
+        Some(p) => std::path::Path::new(&p).exists(),
+        None => true,
+    }
 }
 
 /// Decide whether `track` can play under the CURRENT offline status.
-/// Online → always playable (the normal path pays one status read).
+/// Local / ephemeral user files → existence-checked regardless of
+/// online/offline (the library never hides network-folder content — see
+/// local_library.rs's NETWORK-FOLDER VISIBILITY note — so an unmounted
+/// drive is caught here, at playback time).
+/// Online → otherwise always playable (the normal path pays one status read).
 /// Offline:
-/// - local / ephemeral → playable (file presence is the player's own
-///   failure path)
 /// - plex → induced offline only (a LAN Plex server may be reachable;
 ///   under real offline it is not — Tauri parity)
 /// - qobuz (incl. "qobuz_download" copies, which keep the real Qobuz id)
 ///   → offline-cached AND within the D4 subscription grace window
 fn offline_playability(track: &QueueTrack) -> OfflinePlayability {
+    if matches!(track.source.as_deref(), Some("local") | Some("ephemeral")) {
+        return if local_track_file_exists(track) {
+            OfflinePlayability::Playable
+        } else {
+            OfflinePlayability::FileMissing
+        };
+    }
     let status = crate::offline_mode::engine().status();
     if !status.is_offline() {
         return OfflinePlayability::Playable;
@@ -241,7 +283,7 @@ fn offline_playability(track: &QueueTrack) -> OfflinePlayability {
         return OfflinePlayability::Playable;
     }
     match track.source.as_deref() {
-        Some("local") | Some("ephemeral") => OfflinePlayability::Playable,
+        // ("local" / "ephemeral" never reach here — handled above.)
         Some("plex") => {
             if status.mode == qbz_app::offline_mode::OfflineMode::InducedOffline {
                 OfflinePlayability::Playable
@@ -266,12 +308,14 @@ fn offline_track_playable(track: &QueueTrack) -> bool {
     offline_playability(track) == OfflinePlayability::Playable
 }
 
-/// Move the queue cursor forward/backward to the next offline-playable
-/// track. Online this returns the immediate neighbor on the first
-/// iteration. Offline it skips unavailable tracks, bounded at
-/// [`MAX_OFFLINE_SKIPS`] consecutive (Tauri #467 parity); on exhaustion
-/// (bound hit, or queue edge after at least one skip) playback stops and
-/// ONE toast reports it.
+/// Move the queue cursor forward/backward to the next playable track.
+/// Online this returns the immediate neighbor on the first iteration unless
+/// that neighbor is a LOCAL file whose path is gone (unmounted drive) — the
+/// only possible online skip. Offline it also skips unavailable tracks.
+/// Bounded at [`MAX_OFFLINE_SKIPS`] consecutive (Tauri #467 parity); on
+/// exhaustion (bound hit, or queue edge after at least one skip) playback
+/// stops and ONE toast reports it — worded for the drive when every skip was
+/// a missing local file, for offline otherwise.
 ///
 /// The gapless-prefetched target never passes through here: a gapless
 /// hand-off happens inside the audio engine and surfaces to the poll loop
@@ -283,6 +327,17 @@ async fn advance_to_playable(
     forward: bool,
 ) -> Option<QueueTrack> {
     let mut skips = 0usize;
+    let mut missing_files = 0usize;
+    // One message for the whole walk: when every skipped track was a local
+    // file that isn't on disk, point at the drive; any other mix keeps the
+    // offline wording (online, FileMissing is the only possible skip).
+    let walk_toast = |skips: usize, missing_files: usize| {
+        if missing_files == skips {
+            "Files not available — is the drive mounted?"
+        } else {
+            "No tracks available offline"
+        }
+    };
     loop {
         let step = if forward {
             runtime.core().next_track().await
@@ -295,27 +350,29 @@ async fn advance_to_playable(
             if skips > 0 {
                 crate::toast::show_weak(
                     weak,
-                    "No tracks available offline",
+                    walk_toast(skips, missing_files),
                     crate::ToastKind::Warning,
                 );
             }
             return None;
         };
-        if offline_track_playable(&track) {
-            return Some(track);
+        match offline_playability(&track) {
+            OfflinePlayability::Playable => return Some(track),
+            OfflinePlayability::FileMissing => missing_files += 1,
+            _ => {}
         }
         skips += 1;
         log::info!(
-            "[qbz-slint] offline: skipping unavailable track {} ({skips}/{MAX_OFFLINE_SKIPS})",
+            "[qbz-slint] advance: skipping unavailable track {} ({skips}/{MAX_OFFLINE_SKIPS})",
             track.id
         );
         if skips >= MAX_OFFLINE_SKIPS {
             if let Err(e) = runtime.core().stop() {
-                log::warn!("[qbz-slint] offline: stop after skip bound failed: {e}");
+                log::warn!("[qbz-slint] advance: stop after skip bound failed: {e}");
             }
             crate::toast::show_weak(
                 weak,
-                "No tracks available offline",
+                walk_toast(skips, missing_files),
                 crate::ToastKind::Warning,
             );
             return None;
@@ -359,6 +416,17 @@ async fn play_audible(runtime: &Runtime, weak: &slint::Weak<AppWindow>, track_id
                         );
                         return;
                     }
+                    OfflinePlayability::FileMissing => {
+                        log::info!(
+                            "[qbz-slint] local play: refused track {track_id} (file missing — unmounted drive?)"
+                        );
+                        crate::toast::show_weak(
+                            weak,
+                            "File not available — is the drive mounted?",
+                            crate::ToastKind::Warning,
+                        );
+                        return;
+                    }
                 }
             }
         }
@@ -482,13 +550,30 @@ async fn play_local_file_audible(
         clear_loading(weak, row_id);
         return;
     };
+    // PLAYBACK LOCK (owner verdict 2026-06-10): the library never hides
+    // network-folder content, so an unmounted drive surfaces HERE — one cheap
+    // `Path::exists()` stat before the read, with friendly feedback instead
+    // of a silent log-only failure. Runs inside spawn_blocking, never on the
+    // audio callback thread: an unmounted path returns false instantly; only
+    // a dead-but-still-mounted NFS/CIFS share could block, and then it blocks
+    // a pool thread, not audio (see `local_track_file_exists`).
     let read_path = path.clone();
-    let bytes = tokio::task::spawn_blocking(move || std::fs::read(&read_path))
-        .await
-        .ok()
-        .and_then(Result::ok);
+    let bytes = tokio::task::spawn_blocking(move || {
+        if !std::path::Path::new(&read_path).exists() {
+            return None;
+        }
+        std::fs::read(&read_path).ok()
+    })
+    .await
+    .ok()
+    .flatten();
     let Some(bytes) = bytes else {
-        log::error!("[qbz-slint] local play: failed to read {path}");
+        log::error!("[qbz-slint] local play: file not available at {path}");
+        crate::toast::show_weak(
+            weak,
+            "File not available — is the drive mounted?",
+            crate::ToastKind::Warning,
+        );
         clear_loading(weak, row_id);
         return;
     };

crates/qbz-slint/src/settings.rs

@@ -754,19 +754,12 @@ pub async fn handle_bool(
     value: bool,
 ) {
     let key = key.as_str();
-    // Offline-MODE toggles persist through the shared engine's per-user
+    // The offline-MODE toggle persists through the shared engine's per-user
     // store, not the audio/playback stores — routed apart from the Apply
     // machinery below.
-    match key {
-        "offline-mode-enabled" => {
-            set_offline_mode(ctx, runtime, weak, value).await;
-            return;
-        }
-        "offline-show-network-folders" => {
-            set_offline_network_folders(weak, value);
-            return;
-        }
-        _ => {}
+    if key == "offline-mode-enabled" {
+        set_offline_mode(ctx, runtime, weak, value).await;
+        return;
     }
     // Cross-setting cascades — force dependent settings off and persist
     // those forced changes. `cascaded` flags whether a full snapshot
@@ -944,25 +937,6 @@ async fn set_offline_mode(
     }
 }
 
-/// Settings > Offline — the Show Network Folder Content policy toggle
-/// (visible only while induced offline is on). Pure persistence; the
-/// gating slice consumes the flag.
-fn set_offline_network_folders(weak: slint::Weak<AppWindow>, value: bool) {
-    let engine = crate::offline_mode::engine();
-    if let Err(e) = engine.set_show_network_folders(value) {
-        log::error!("[qbz-slint] show-network-folders toggle failed: {e}");
-        // Revert the optimistic toggle to the persisted state.
-        let actual = engine
-            .settings()
-            .map(|s| s.show_network_folders_in_manual_offline)
-            .unwrap_or(!value);
-        let _ = weak.upgrade_in_event_loop(move |w| {
-            w.global::<SettingsState>()
-                .set_offline_show_network_folders(actual);
-        });
-    }
-}
-
 /// Handle a slider change: persist it and reload the player settings.
 /// Currently only the Initial Buffer Size slider exists.
 pub fn handle_slider(

crates/qbz-slint/ui/settings/OfflineSettings.slint

@@ -119,19 +119,6 @@ export component OfflineSettings inherits VerticalLayout {
             }
         }
     }
-    // The network-folders policy only applies while induced offline is on,
-    // so the row only mounts then (Tauri parity; ADR-010 conditional mount).
-    if SettingsState.offline-mode-enabled: SettingRow {
-        label: @tr("Show Network Folder Content");
-        description: @tr("Display content from network-mounted folders (NAS, Samba, etc.) while in offline mode.");
-        QbzToggle {
-            checked: SettingsState.offline-show-network-folders;
-            toggled(v) => {
-                SettingsState.offline-show-network-folders = v;
-                root.settings-bool("offline-show-network-folders", v);
-            }
-        }
-    }
 
     Rectangle { height: 12px; }
     Divider { }