Solo watching and a clearer offline start

Putting anything up offline starts a solo session: an in-app server bound
to 127.0.0.1 only, joined like hosting, so tracking, next episode and the
player all work. Invite friends re-hosts on the Host card's port and
password with the same media and position; Stop needs no confirmation.
Offline, the Library opens with a welcome band (Join a friend, Host, Watch
solo); without a Jellyfin account it leads with Files and Link, Jellyfin
is an optional card. Play buttons work offline.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -41,12 +41,28 @@ release with a newer protocol is a required update: everyone on a server
 must run the same protocol version, and a mismatch is refused with a message
 telling you to update.
 
+## Getting started
+
+Three ways in, all at the top of the Library when you are not in a server.
+None of them needs Jellyfin or an account.
+
+- **Join a friend** (most people): your friend sends you an address and,
+  maybe, a password. See [Join](#join).
+- **Host**: you have the video and friends watch it with you. See
+  [Host from the app](#host-from-the-app).
+- **Watch solo**: just play something from the Library. It plays for you
+  alone, with everything a server has (Jellyfin progress, next episode,
+  skip buttons); nothing is reachable from outside this computer. Invite
+  friends in the strip turns it into a hosted server (the Host card's port
+  and password) and the video carries on from where it was; Stop ends it.
+
 ## The window
 
 One window. Along the top, the strip: your avatar (click it for your
 profile: name, picture with a crop editor, colour, and links to the
 settings), the Library / Schedule / Settings tabs, and the party. Offline
-the party side has Join and Host; in a server it shows everyone's avatar
+the party side has Join a friend and Host; watching solo it says Solo,
+with Invite friends and Stop; in a server it shows everyone's avatar
 with a ring for their state (green ready, amber buffering, grey not ready,
 dimmed reconnecting, dimmed with a moon sitting out; a crown on whoever
 hosts, a tower on whoever passes the video on). Click the avatars for the
@@ -108,7 +124,8 @@ a folder or a link anywhere on the window, or press Ctrl+V outside a
 text field, and a small card asks how to open it (put it up, add the
 folder to Files, or fill Link).
 
-- **Jellyfin**: your linked servers (see below). Library chips beside the
+- **Jellyfin**: your linked servers (see below); with none linked it
+  points to Files and Link and offers Jellyfin as optional. Library chips beside the
   switch, then one **Continue** row (what you were watching and what comes
   next, one card per series, the one you watched most recently first;
   series not touched for two months drop out) and **Latest in** each
@@ -129,8 +146,8 @@ folder to Files, or fill Link).
 - **Files**: video folders you add on this computer, grouped by series
   (click a series to list its episodes), or any file through Browse. The others stream it from you.
 
-Put it up and the player opens. Offline the library browses but nothing
-goes up until you join or host ("Join or host to watch together").
+Put it up and the player opens. Not in a server, the buttons say Play
+and it plays for you alone ([Watch solo](#getting-started)).
 
 ## Dedicated server
 

apps/desktop/lib/src/files/ui/file_tiles.dart

@@ -10,9 +10,6 @@ import 'thumb.dart';
 // The Files page's rows and cards: a series header, an episode row (also
 // used for Recent), a loose-video card, and the empty states.
 
-/// Shown on play controls while there is nobody to watch with.
-const offlinePlayHint = 'Join or host to watch';
-
 /// What a play control is doing right now.
 enum PlayState { idle, starting, playing }
 
@@ -28,10 +25,6 @@ String parentName(String path) => baseName(File(path).parent.path);
 /// Cleaned title of a loose video: `Title (2019)`.
 String cleanTitle(ParsedName p) => p.year == null ? p.series : '${p.series} (${p.year})';
 
-/// Disabled with [offlinePlayHint] when [onTap] is null because offline.
-Widget _offlineTip(bool offline, Widget child) =>
-    offline ? Tooltip(message: offlinePlayHint, child: child) : child;
-
 class SeriesHeader extends StatelessWidget {
   final SeriesGroup group;
   final ThumbCache thumbs;
@@ -110,9 +103,8 @@ class FileRow extends StatelessWidget {
   final String? size;
   final PlayState state;
   final ThumbCache thumbs;
-  /// Null disables the row ([offline] adds the reason as a tooltip).
+  /// Null disables the row.
   final VoidCallback? onTap;
-  final bool offline;
   final bool indent;
   final Widget? trailing;
   const FileRow({
@@ -124,7 +116,6 @@ class FileRow extends StatelessWidget {
     required this.state,
     required this.thumbs,
     required this.onTap,
-    required this.offline,
     this.indent = true,
     this.trailing,
   });
@@ -148,9 +139,7 @@ class FileRow extends StatelessWidget {
       builder: (context, t, _) {
         final duration = durationText(t);
         final meta = [?duration, ?size].join(' · ');
-        return _offlineTip(
-          offline,
-          Material(
+        return Material(
           color: playing ? scheme.primary.withValues(alpha: 0.08) : Colors.transparent,
           borderRadius: BorderRadius.circular(10),
           child: InkWell(
@@ -206,7 +195,6 @@ class FileRow extends StatelessWidget {
               ),
             ),
           ),
-          ),
         );
       },
     );
@@ -223,14 +211,12 @@ class VideoCard extends StatelessWidget {
   final PlayState state;
   final ThumbCache thumbs;
   final VoidCallback? onTap;
-  final bool offline;
   const VideoCard({
     super.key,
     required this.video,
     required this.state,
     required this.thumbs,
     required this.onTap,
-    required this.offline,
   });
 
   @override
@@ -242,9 +228,7 @@ class VideoCard extends StatelessWidget {
       path: video.path,
       builder: (context, t, _) {
         final duration = durationText(t);
-        return _offlineTip(
-          offline,
-          InkWell(
+        return InkWell(
           onTap: onTap,
           borderRadius: BorderRadius.circular(12),
           child: Column(
@@ -301,7 +285,6 @@ class VideoCard extends StatelessWidget {
                   style: TextStyle(color: scheme.onSurfaceVariant, fontSize: 12)),
             ],
           ),
-          ),
         );
       },
     );

apps/desktop/lib/src/files/ui/files_page.dart

@@ -48,8 +48,8 @@ void resetFilesPageSession() {
 }
 
 class FilesPage extends StatefulWidget {
-  /// In a session: false disables playing (browsing still works).
-  final bool online;
+  /// Nobody else watches (offline or solo): no relay notice.
+  final bool solo;
   /// The file will stream from this computer through the server.
   final bool relayed;
   /// Plays [path] in the session; returns an error text, or null.
@@ -67,7 +67,7 @@ class FilesPage extends StatefulWidget {
 
   const FilesPage({
     super.key,
-    required this.online,
+    this.solo = false,
     required this.relayed,
     required this.onPlay,
     this.nowPlayingPath,
@@ -207,7 +207,7 @@ class _FilesPageState extends State<FilesPage> {
   }
 
   Future<void> _play(String path) async {
-    if (!widget.online || _starting != null) return;
+    if (_starting != null) return;
     setState(() {
       _starting = path;
       _error = null;
@@ -236,7 +236,7 @@ class _FilesPageState extends State<FilesPage> {
           ? PlayState.playing
           : PlayState.idle;
 
-  VoidCallback? _tapOf(String path) => widget.online ? () => _play(path) : null;
+  VoidCallback _tapOf(String path) => () => _play(path);
 
   @override
   Widget build(BuildContext context) => LayoutBuilder(
@@ -264,9 +264,7 @@ class _FilesPageState extends State<FilesPage> {
         },
       );
 
-  Widget _browseButton(Widget Function(VoidCallback? onPressed) build) => widget.online
-      ? build(_browse)
-      : Tooltip(message: offlinePlayHint, child: build(null));
+  Widget _browseButton(Widget Function(VoidCallback? onPressed) build) => build(_browse);
 
   Widget _sidebar(BuildContext context, List<String> folders, String? open) {
     final scheme = Theme.of(context).colorScheme;
@@ -345,7 +343,7 @@ class _FilesPageState extends State<FilesPage> {
     final top = <Widget>[
       _header(context, open),
       if (narrow) _chips(folders, open),
-      if (widget.online && widget.relayed) const _RelayNotice(),
+      if (!widget.solo && widget.relayed) const _RelayNotice(),
       AnimatedSize(
         duration: easeTime,
         curve: ease,
@@ -476,7 +474,6 @@ class _FilesPageState extends State<FilesPage> {
             state: _stateOf(path),
             thumbs: _thumbs,
             onTap: _tapOf(path),
-            offline: !widget.online,
             onRemove: () => _store.removeRecent(path),
           );
         },
@@ -594,7 +591,6 @@ class _FilesPageState extends State<FilesPage> {
             state: _stateOf(v.path),
             thumbs: _thumbs,
             onTap: _tapOf(v.path),
-            offline: !widget.online,
           );
         },
       ),
@@ -630,7 +626,6 @@ class _FilesPageState extends State<FilesPage> {
                 state: _stateOf(v.path),
                 thumbs: _thumbs,
                 onTap: _tapOf(v.path),
-                offline: !widget.online,
               );
             },
           );
@@ -647,7 +642,6 @@ class _RecentRow extends StatefulWidget {
   final PlayState state;
   final ThumbCache thumbs;
   final VoidCallback? onTap;
-  final bool offline;
   final VoidCallback onRemove;
   const _RecentRow({
     super.key,
@@ -655,7 +649,6 @@ class _RecentRow extends StatefulWidget {
     required this.state,
     required this.thumbs,
     required this.onTap,
-    required this.offline,
     required this.onRemove,
   });
 
@@ -688,7 +681,6 @@ class _RecentRowState extends State<_RecentRow> {
       state: widget.state,
       thumbs: widget.thumbs,
       onTap: missing ? null : widget.onTap,
-      offline: widget.offline && !missing,
       indent: false,
       trailing: IconButton(
         tooltip: 'Remove from recent',

apps/desktop/lib/src/jellyfin/details_panel.dart

@@ -32,16 +32,16 @@ typedef _Data = ({
 });
 
 /// The selected card's details, at the right of the library: banner,
-/// title, meta, "Put it up · S1E3" (a disabled Play with [offlineHint]
-/// offline), mark watched / unwatched, remove from Continue, overview and,
+/// title, meta, "Put it up · S1E3" ("Play · S1E3" when watching
+/// [solo]), mark watched / unwatched, remove from Continue, overview and,
 /// for a series or an episode, the episode list (click picks which
 /// episode goes up, double-click puts it up). Reloads when the
 /// [controller]'s data version moves.
 class JellyfinDetailsPanel extends StatefulWidget {
   final BrowseController controller;
   final JellyfinSelection selection;
-  /// Null when online; else why nothing can go up.
-  final String? offlineHint;
+  /// Nobody else watches (offline or solo): the button says Play.
+  final bool solo;
   /// Puts [item] (playable) up; returns an error text, or null when sent.
   final Future<String?> Function(JellyfinSelection item) onPutUp;
   final VoidCallback onClose;
@@ -51,7 +51,7 @@ class JellyfinDetailsPanel extends StatefulWidget {
     required this.selection,
     required this.onPutUp,
     required this.onClose,
-    this.offlineHint,
+    this.solo = false,
   });
 
   @override
@@ -104,7 +104,7 @@ class _JellyfinDetailsPanelState extends State<JellyfinDetailsPanel> {
       _cached('episodes:$seriesId:$seasonId', (c) => c.episodes(seriesId, seasonId: seasonId));
 
   Future<void> _putUp(JellyfinItem target) async {
-    if (_busy || widget.offlineHint != null) return;
+    if (_busy) return;
     setState(() {
       _busy = true;
       _error = null;
@@ -253,14 +253,8 @@ class _JellyfinDetailsPanelState extends State<JellyfinDetailsPanel> {
       if (shown.communityRating != null) '★ ${shown.communityRating!.toStringAsFixed(1)}',
       if (!isSeries && shown.userData.played) 'Watched',
     ].join(' · ');
-    final hint = widget.offlineHint;
-    final label = playable == null
-        ? (hint == null ? 'Put it up' : 'Play')
-        : hint != null
-            ? 'Play'
-            : isSeries
-                ? 'Put it up · ${playable.episodeLabel ?? playable.name}'
-                : 'Put it up';
+    final verb = widget.solo ? 'Play' : 'Put it up';
+    final label = playable != null && isSeries ? '$verb · ${playable.episodeLabel ?? playable.name}' : verb;
     final inContinue = playable != null &&
         (playable.userData.isResumable || _c.continueKeys.contains(continueKey(playable)));
     final left = playable == null ? null : timeLeft(playable);
@@ -307,7 +301,7 @@ class _JellyfinDetailsPanelState extends State<JellyfinDetailsPanel> {
                 children: [
                   FilledButton.icon(
                     key: const ValueKey('details-put-up'),
-                    onPressed: playable == null || hint != null || _busy ? null : () => _putUp(playable),
+                    onPressed: playable == null || _busy ? null : () => _putUp(playable),
                     icon: _busy
                         ? const SizedBox.square(dimension: 16, child: CircularProgressIndicator(strokeWidth: 2))
                         : const Icon(Icons.play_arrow),
@@ -336,12 +330,12 @@ class _JellyfinDetailsPanelState extends State<JellyfinDetailsPanel> {
                     ),
                 ],
               ),
-              if (hint != null || _error != null) ...[
+              if (_error != null) ...[
                 const SizedBox(height: 6),
                 Text(
-                  _error ?? hint!,
+                  _error!,
                   key: const ValueKey('details-hint'),
-                  style: t.bodySmall?.copyWith(color: _error != null ? scheme.error : Colors.grey),
+                  style: t.bodySmall?.copyWith(color: scheme.error),
                 ),
               ],
               if (isSeries && playable != null) ...[

apps/desktop/lib/src/jellyfin/picker_source.dart

@@ -7,7 +7,7 @@ import 'browser.dart';
 import 'sign_in_panel.dart';
 
 /// The Library's Jellyfin source: the library browser once a server is
-/// linked, else an inline add-server panel.
+/// linked, else [empty] (default: an inline add-server panel).
 class JellyfinPickerSource extends StatefulWidget {
   final JellyfinAccounts accounts;
   final BrowseController? controller;
@@ -17,6 +17,8 @@ class JellyfinPickerSource extends StatefulWidget {
   final VoidCallback? onOpenIntegrations;
   final BrowseStart? start;
   final bool libraryStrip;
+  /// Shown while no server is linked.
+  final WidgetBuilder? empty;
   const JellyfinPickerSource({
     super.key,
     this.start,
@@ -27,6 +29,7 @@ class JellyfinPickerSource extends StatefulWidget {
     this.selected,
     this.onOpenIntegrations,
     this.libraryStrip = true,
+    this.empty,
   });
 
   @override
@@ -49,6 +52,7 @@ class _JellyfinPickerSourceState extends State<JellyfinPickerSource> {
         if (!a.loaded) {
           return const Center(child: CircularProgressIndicator(strokeWidth: 2));
         }
+        if (a.isEmpty && widget.empty != null) return widget.empty!(context);
         if (a.isEmpty) return _LinkFirst(accounts: a, onOpenIntegrations: widget.onOpenIntegrations);
         return JellyfinBrowser(
           key: const ValueKey('media-jellyfin'),

apps/desktop/lib/src/schedule/ui/schedule_card.dart

@@ -13,8 +13,8 @@ enum CardAction {
   none,
   putUp,
 
-  /// Available, but not in a server: shown disabled with a hint.
-  playOffline,
+  /// Available, nobody else watching (offline or solo): plays it here.
+  play,
   request,
   requestSeries,
   requested,
@@ -162,15 +162,10 @@ class AiringCard extends StatelessWidget {
     final spinner = const SizedBox(width: 16, height: 16, child: CircularProgressIndicator(strokeWidth: 2));
     Widget? b = switch (action) {
       CardAction.none => null,
-      CardAction.putUp => FilledButton.tonalIcon(
+      CardAction.putUp || CardAction.play => FilledButton.tonalIcon(
         onPressed: enabled ? onAction : null,
         icon: busy ? spinner : const Icon(Icons.play_arrow, size: 18),
-        label: const Text('Put it up'),
-      ),
-      CardAction.playOffline => FilledButton.tonalIcon(
-        onPressed: null,
-        icon: const Icon(Icons.play_arrow, size: 18),
-        label: const Text('Play'),
+        label: Text(action == CardAction.play ? 'Play' : 'Put it up'),
       ),
       CardAction.request || CardAction.requestSeries => OutlinedButton.icon(
         onPressed: enabled ? onAction : null,
@@ -216,7 +211,7 @@ class AiringCard extends StatelessWidget {
         ),
       ),
     );
-    final tap = action == CardAction.putUp && disabledHint == null && !busy ? onAction : null;
+    final tap = (action == CardAction.putUp || action == CardAction.play) && disabledHint == null && !busy ? onAction : null;
     if (compact) {
       final requestable = action == CardAction.request || action == CardAction.requestSeries;
       return Material(

apps/desktop/lib/src/schedule/ui/schedule_page.dart

@@ -21,8 +21,9 @@ import 'schedule_card.dart';
 enum ScheduleFilter { jellyfin, following, all }
 
 class SchedulePage extends StatefulWidget {
-  /// In a server: available episodes can be put up.
-  final bool online;
+  /// Nobody else watches (offline or solo): available episodes say Play
+  /// (offline that starts a solo session).
+  final bool solo;
 
   /// Puts a Jellyfin episode up in the server; returns an error to show.
   final Future<String?> Function(JellyfinMedia pick) onPutUp;
@@ -36,7 +37,7 @@ class SchedulePage extends StatefulWidget {
 
   const SchedulePage({
     super.key,
-    required this.online,
+    this.solo = false,
     required this.onPutUp,
     required this.onToast,
     this.repository,
@@ -215,9 +216,9 @@ class _SchedulePageState extends State<SchedulePage> {
 
   (CardAction, String?) _actionFor(ScheduleEntry e) {
     if (e.status == ScheduleStatus.available || e.status == ScheduleStatus.inLibrary) {
-      if (!widget.online) return (CardAction.playOffline, 'Join or host a server to put it up');
-      if (e.jellyfinSeriesId == null) return (CardAction.putUp, 'Not linked to a Jellyfin series yet');
-      return (CardAction.putUp, null);
+      final put = widget.solo ? CardAction.play : CardAction.putUp;
+      if (e.jellyfinSeriesId == null) return (put, 'Not linked to a Jellyfin series yet');
+      return (put, null);
     }
     final me = _me;
     final CardAction kind;
@@ -242,6 +243,7 @@ class _SchedulePageState extends State<SchedulePage> {
   Future<void> _onAction(ScheduleEntry e, CardAction action) async {
     switch (action) {
       case CardAction.putUp:
+      case CardAction.play:
         return _putUp(e);
       case CardAction.request:
       case CardAction.requestSeries:
@@ -530,7 +532,7 @@ class _SchedulePageState extends State<SchedulePage> {
 
   Widget _card(ScheduleEntry e, DateTime now) {
     final (action, hint) = _actionFor(e);
-    final busy = _busy.contains(action == CardAction.putUp ? 'play:${_key(e)}' : _key(e));
+    final busy = _busy.contains(action == CardAction.putUp || action == CardAction.play ? 'play:${_key(e)}' : _key(e));
     return AiringCard(
       entry: e,
       now: now,

apps/desktop/lib/src/session/session_coordinator.dart

@@ -277,6 +277,10 @@ class SessionCoordinator {
   int _relaySourceMediaId = -1;
   /// This member serves the current media's bytes through the server.
   final relaying = signal<bool>(false);
+  /// What this client put up last in this connection (a solo session
+  /// carries it over when it becomes a hosted server).
+  PickedMedia? get lastPick => _lastPick;
+  PickedMedia? _lastPick;
   // Server seek applied to the player (event id and when), checked once it
   // should have landed.
   int? _pendingSeekEvent;
@@ -402,6 +406,7 @@ class SessionCoordinator {
     _seekGate.reset();
     _clearPendingSeek();
     _lastEventId = -1;
+    _lastPick = null;
     _resetJellyfin();
     _jfToastShown = false;
     if (!_jellyfinListening) {
@@ -1235,6 +1240,7 @@ class SessionCoordinator {
   /// link, or relayed per [relay]. Returns an error text, or null when sent.
   Future<String?> swapLink(String url, {LinkRelay relay = LinkRelay.direct}) async {
     markInput();
+    _lastPick = LinkMedia(url, relay: relay);
     final media = await mediaForLink(jellyfin, url);
     if (media.jellyfin != null) {
       _pendingOrigin = _JellyfinOrigin(url);
@@ -1304,6 +1310,7 @@ class SessionCoordinator {
   /// relayed by this member for viewers without an account.
   void swapJellyfin(JellyfinMedia media) {
     markInput();
+    _lastPick = media;
     _pendingOrigin = const _JellyfinOrigin(null);
     _swap(mediaForPick(media).copyWith(relay: const MediaRelay()));
   }
@@ -1313,6 +1320,7 @@ class SessionCoordinator {
   /// when sent.
   Future<String?> swapFile(String path) async {
     markInput();
+    _lastPick = FileMedia(path);
     final host = hostFile;
     if (host != null) {
       final file = await host(path);

apps/desktop/lib/src/shell/app_shell.dart

@@ -13,6 +13,7 @@ import '../jellyfin/accounts.dart';
 import '../jellyfin/browse_scope.dart' show BrowseStart;
 import '../jellyfin/session_media.dart';
 import '../screens/home/connect_flow.dart';
+import '../session/session_coordinator.dart' show ConnectParams;
 import '../screens/home/health_probe.dart';
 import '../screens/home/media_picker.dart';
 import '../screens/home/profile.dart';
@@ -31,6 +32,7 @@ import '../schedule/ui/schedule_page.dart';
 import 'session_player.dart';
 import 'settings_tab.dart';
 import 'toasts.dart';
+import 'welcome.dart';
 
 /// The one window: the party strip over a body that fades through between
 /// the tabs and the full player, the floating mini player, the chat panel
@@ -116,6 +118,11 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
   final _stops = <void Function()>[];
   // Rebuild the shell on these flips, not on every state broadcast.
   final _online = computed(() => SessionState.instance.route.value == AppRoute.session);
+  /// Nobody else watches: offline, solo, or solo becoming a server.
+  final _alone = computed(() {
+    final s = SessionState.instance;
+    return s.route.value != AppRoute.session || s.solo.value || s.switching.value;
+  });
   final _hasMedia = computed(() =>
       SessionState.instance.route.value == AppRoute.session &&
       SessionState.instance.coordinator.serverState.value?.media != null);
@@ -190,6 +197,17 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
       }
       wasOut = out;
     }));
+    // Solo becoming a hosted server: the player closes while the media
+    // moves over and comes back the way it was once it is up again.
+    _stops.add(effect(() {
+      if (!session.switching.value) return;
+      _later(() {
+        _lastMediaId = -1;
+        _autoFull = _mode == PlayerMode.full;
+        if (_fullscreen) _toggleFullscreen();
+        _show(PlayerMode.none);
+      });
+    }));
     // The hosted server died mid-session (SessionState leaves): say so.
     _stops.add(effect(() {
       final crash = session.serverCrash.value;
@@ -209,6 +227,7 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
     HardwareKeyboard.instance.removeHandler(_onKey);
     _fade.dispose();
     _online.dispose();
+    _alone.dispose();
     _hasMedia.dispose();
     _flow.dispose();
     _join.dispose();
@@ -343,7 +362,8 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
     _selectTab(ShellTab.library);
   }
 
-  /// Library → "Put it up for everyone"; the player opens full.
+  /// Library → "Put it up for everyone"; the player opens full. Offline
+  /// it starts a solo session first (just you, on this computer).
   Future<String?> _putUp(PickedMedia media) async {
     final session = SessionState.instance;
     if (media is JellyfinMedia) {
@@ -354,6 +374,12 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
       }
       unawaited(_jellyfin.rememberPick(media));
     }
+    if (!_online.peek()) {
+      final error = await _startSolo();
+      if (error != null || !mounted) return error;
+    }
+    // Alone, a link plays direct: there is nobody to pass it on to.
+    if (media is LinkMedia && session.solo.peek()) media = LinkMedia(media.url);
     final error = await session.coordinator.swapPicked(media);
     if (error != null || !mounted) return error;
     final f = session.lastForm;
@@ -366,6 +392,29 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
     return null;
   }
 
+  /// Starts a solo session; returns an error text, or null.
+  Future<String?> _startSolo() async {
+    final profile = Profile.instance;
+    try {
+      await profile.ensureLoaded();
+      final name = profile.name.peek().trim();
+      await SessionState.instance.startSolo(ConnectParams(
+        host: '127.0.0.1',
+        port: 0,
+        secret: '',
+        name: name.isEmpty ? 'Me' : name,
+        avatar: profile.avatarBase64(),
+      ));
+      return null;
+    } catch (e) {
+      return "couldn't start playing: $e";
+    }
+  }
+
+  /// Library's "Watch solo": somewhere to pick from (Jellyfin when linked,
+  /// else Files).
+  void _watchSolo() => _openLibrary(_jellyfin.isEmpty ? MediaKind.file : MediaKind.jellyfin);
+
   // --------------------------------------------------------------- handoff
 
   /// Nothing (a dialog, a popover) is over the shell.
@@ -406,11 +455,10 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
     final align = at == null || size.isEmpty
         ? Alignment.center
         : Alignment((at.dx / size.width * 2 - 1).clamp(-1, 1), (at.dy / size.height * 2 - 1).clamp(-1, 1));
-    final online = _online.peek();
     _handoffOpen = true;
     final HandoffAction? action;
     try {
-      action = await showPopover<HandoffAction>(context, at: align, child: HandoffCard(item: item, online: online));
+      action = await showPopover<HandoffAction>(context, at: align, child: HandoffCard(item: item, solo: _alone.peek()));
     } finally {
       _handoffOpen = false;
     }
@@ -424,10 +472,6 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
           await FolderStore.instance.ensureLoaded();
           FolderStore.instance.addRecent(paths.first);
         }
-      case (HandoffVideos(:final paths), HandoffAction.openInFiles):
-        await FolderStore.instance.ensureLoaded();
-        FolderStore.instance.addRecent(paths.first);
-        _openFiles(null);
       case (HandoffVideos(:final paths), HandoffAction.addFolder):
         await _addFolder(File(paths.first).parent.path);
       case (HandoffFolder(:final path), _):
@@ -484,7 +528,13 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
 
   // --------------------------------------------------------------- dialogs
 
+  /// Leave asks first; a solo session just stops.
   Future<void> _confirmLeave() async {
+    final session = SessionState.instance;
+    if (session.solo.peek()) {
+      await session.leave();
+      return;
+    }
     final ok = await showDialog<bool>(
       context: context,
       builder: (context) => AlertDialog(
@@ -542,6 +592,7 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
         backgroundColor: _fullscreen ? Colors.black : scheme.surface,
         body: SignalBuilder(builder: (context) {
           final online = _online.value;
+          final alone = _alone.value;
           final hasMedia = _hasMedia.value;
           return Column(
             children: [
@@ -556,6 +607,7 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
                   onJoin: () => _connect(ConnectMode.join),
                   onHost: () => _connect(ConnectMode.host),
                   onLeave: _confirmLeave,
+                  onInvite: () => _connect(ConnectMode.host),
                   onProfile: () => showProfileCard(context, onOpenSettings: _openSettings, updates: widget.updates),
                   onShowPlayer: hasMedia && _mode == PlayerMode.none ? () => _show(PlayerMode.mini) : null,
                   updates: widget.updates,
@@ -565,7 +617,7 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
                 key: const ValueKey('body'),
                 child: Row(
                   children: [
-                    Expanded(child: _body(online)),
+                    Expanded(child: _body(online, alone)),
                     AnimatedSize(
                       duration: easeTime,
                       curve: ease,
@@ -589,21 +641,29 @@ class AppShellState extends State<AppShell> with SingleTickerProviderStateMixin
     );
   }
 
-  Widget _body(bool online) {
+  Widget _body(bool online, bool alone) {
     final coord = SessionState.instance.coordinator;
     final tabBody = switch (_tab) {
       ShellTab.library => LibraryTab(
           key: ValueKey('library-$_libraryGen'),
           controller: _picker,
           accounts: _jellyfin,
-          online: online,
-          isHost: coord.hostFile != null,
+          solo: alone,
+          // Offline, a put-up starts a solo session, which hosts.
+          isHost: !online || coord.hostFile != null,
+          banner: online
+              ? null
+              : WelcomeBand(
+                  onJoin: () => _connect(ConnectMode.join),
+                  onHost: () => _connect(ConnectMode.host),
+                  onSolo: _watchSolo,
+                ),
           jellyfinStart: _libraryStart,
           onPutUp: _putUp,
           onOpenIntegrations: () => _openSettings(SettingsSection.integrations),
         ),
       ShellTab.schedule => SchedulePage(
-          online: online,
+          solo: alone,
           onPutUp: _putUp,
           onToast: coord.showToast,
         ),

apps/desktop/lib/src/shell/connect_cards.dart

@@ -41,8 +41,9 @@ class HostFields {
   }
 }
 
-/// The strip's Join / Host buttons: a card over the window. It closes
-/// itself once the attempt got in; a failed one shows its error inside.
+/// The strip's Join / Host buttons (and solo's Invite friends, the Host
+/// card): a card over the window. It closes itself once the attempt got
+/// in; a failed one shows its error inside.
 Future<void> showConnectCard(
   BuildContext context, {
   required ConnectMode mode,
@@ -77,7 +78,9 @@ class _CloseWhenOnlineState extends State<_CloseWhenOnline> {
   void initState() {
     super.initState();
     _stop = effect(() {
-      if (SessionState.instance.route.value != AppRoute.session) return;
+      final s = SessionState.instance;
+      // Solo is in a session too: wait until it is a hosted server.
+      if (s.route.value != AppRoute.session || s.solo.value || s.switching.value) return;
       WidgetsBinding.instance.addPostFrameCallback((_) {
         if (mounted) Navigator.of(context).maybePop();
       });
@@ -153,7 +156,7 @@ class JoinCard extends StatelessWidget {
       builder: (context, _) {
         final busy = flow.busy == ConnectMode.join;
         return _Card(
-          title: 'Join a server',
+          title: 'Join a friend',
           children: [
             SignalBuilder(builder: (context) {
               final list = [
@@ -221,6 +224,13 @@ class JoinCard extends StatelessWidget {
             const SizedBox(height: 16),
             ConnectButton(flow: flow, mode: ConnectMode.join, label: 'Join', onSubmit: _join, expand: true),
             ConnectFeedback(flow: flow, mode: ConnectMode.join),
+            const Padding(
+              padding: EdgeInsets.only(top: 8),
+              child: Text(
+                'Your friend gives you the address and password. No account or Jellyfin needed.',
+                style: TextStyle(color: Colors.grey, fontSize: 12),
+              ),
+            ),
           ],
         );
       },
@@ -243,10 +253,13 @@ class HostCard extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    // From a solo session this is "Invite friends": same server settings,
+    // and what plays carries over.
+    final solo = SessionState.instance.solo.peek();
     return ListenableBuilder(
       listenable: flow,
       builder: (context, _) => _Card(
-        title: 'Host a server',
+        title: solo ? 'Invite friends' : 'Host a server',
         children: [
           AbsorbPointer(
             absorbing: flow.busy == ConnectMode.host,
@@ -281,13 +294,16 @@ class HostCard extends StatelessWidget {
             ),
           ),
           const SizedBox(height: 16),
-          ConnectButton(flow: flow, mode: ConnectMode.host, label: 'Host', onSubmit: _host, expand: true),
+          ConnectButton(
+              flow: flow, mode: ConnectMode.host, label: solo ? 'Start hosting' : 'Host', onSubmit: _host, expand: true),
           ConnectFeedback(flow: flow, mode: ConnectMode.host),
-          const Padding(
-            padding: EdgeInsets.only(top: 8),
+          Padding(
+            padding: const EdgeInsets.only(top: 8),
             child: Text(
-              'You pick what to watch afterwards, in the library.',
-              style: TextStyle(color: Colors.grey, fontSize: 12),
+              solo
+                  ? 'Your video keeps playing from where it is; friends join with your address.'
+                  : 'You pick what to watch afterwards, in the library.',
+              style: const TextStyle(color: Colors.grey, fontSize: 12),
             ),
           ),
         ],

apps/desktop/lib/src/shell/handoff.dart

@@ -4,7 +4,6 @@ import 'package:flutter/material.dart';
 
 import '../files/scanner.dart' show FileKind, kindOf;
 import '../files/ui/file_tiles.dart' show baseName;
-import 'library_tab.dart' show offlinePutUpHint;
 
 // Something handed to the app, by a drop or by Ctrl+V outside a text
 // field: what it is ([classifyHandoff], pure) and the small card that asks
@@ -95,10 +94,8 @@ Handoff classifyHandoff({
 
 /// What the card's buttons ask the shell to do.
 enum HandoffAction {
-  /// Put the (first) video up for everyone.
+  /// Put the (first) video up (offline: watch it solo).
   putUp,
-  /// Offline: list the video in Files → Recent and open it there.
-  openInFiles,
   /// Add the video's folder (or the folder) to Files and open it.
   addFolder,
   /// Open Library → Link with the URL filled.
@@ -109,8 +106,9 @@ enum HandoffAction {
 /// pops the [HandoffAction] chosen.
 class HandoffCard extends StatelessWidget {
   final Handoff item;
-  final bool online;
-  const HandoffCard({super.key, required this.item, required this.online});
+  /// Nobody else watches (offline or solo): videos play, no relay talk.
+  final bool solo;
+  const HandoffCard({super.key, required this.item, required this.solo});
 
   @override
   Widget build(BuildContext context) {
@@ -128,10 +126,7 @@ class HandoffCard extends StatelessWidget {
           baseName(paths.first),
           paths.length > 1 ? 'and ${paths.length - 1} more · the first one goes up' : 'A video on this computer',
           [
-            if (online)
-              button(HandoffAction.putUp, Icons.play_arrow, 'Put it up', primary: true)
-            else
-              button(HandoffAction.openInFiles, Icons.history, 'Open in Files', primary: true),
+            button(HandoffAction.putUp, Icons.play_arrow, solo ? 'Play' : 'Put it up', primary: true),
             button(HandoffAction.addFolder, Icons.create_new_folder_outlined, 'Add its folder to Files'),
           ],
         ),
@@ -144,9 +139,9 @@ class HandoffCard extends StatelessWidget {
       HandoffLink(:final url) => (
           Icons.link,
           url,
-          online ? 'Pick how the others get it on the Link page' : offlinePutUpHint,
+          solo ? 'Opens it on the Link page' : 'Pick how the others get it on the Link page',
           [
-            button(HandoffAction.openLink, Icons.link, online ? 'Put it up as a link…' : 'Open in Link',
+            button(HandoffAction.openLink, Icons.link, solo ? 'Open in Link' : 'Put it up as a link…',
                 primary: true),
           ],
         ),

apps/desktop/lib/src/shell/library_link.dart

@@ -189,10 +189,14 @@ String linkRelayHelp(LinkRelay r) => switch (r) {
           'while it plays; the link is not shown to anyone.',
     };
 
-/// The Link source. [offlineHint] set: the button is off and says why.
+/// Under Play when nobody else watches.
+const soloPlayHint = 'Plays just for you. Invite friends any time; it keeps playing.';
+
+/// The Link source. [solo]: nobody else watches (offline or solo), so the
+/// button says Play and there are no relay modes (the link plays direct).
 class LibraryLinkSource extends StatefulWidget {
   final MediaPickerController controller;
-  final String? offlineHint;
+  final bool solo;
   /// Puts the link up; returns an error text, or null when sent.
   final Future<String?> Function(LinkMedia media) onPutUp;
   final RecentLinks recents;
@@ -202,7 +206,7 @@ class LibraryLinkSource extends StatefulWidget {
     required this.controller,
     required this.onPutUp,
     required this.recents,
-    this.offlineHint,
+    this.solo = false,
     this.probe = defaultLinkProber,
   });
 
@@ -261,14 +265,14 @@ class _LibraryLinkSourceState extends State<LibraryLinkSource> {
 
   Future<void> _go() async {
     final url = _c.link.text.trim();
-    if (url.isEmpty || _busy || widget.offlineHint != null) return;
+    if (url.isEmpty || _busy) return;
     setState(() {
       _busy = true;
       _error = null;
     });
     String? error;
     try {
-      error = await widget.onPutUp(LinkMedia(url, relay: _c.linkRelay));
+      error = await widget.onPutUp(LinkMedia(url, relay: widget.solo ? LinkRelay.direct : _c.linkRelay));
     } catch (e) {
       error = '$e';
     }
@@ -292,7 +296,7 @@ class _LibraryLinkSourceState extends State<LibraryLinkSource> {
   Widget build(BuildContext context) {
     final scheme = Theme.of(context).colorScheme;
     final t = Theme.of(context).textTheme;
-    final hint = widget.offlineHint;
+    final solo = widget.solo;
     final url = _c.link.text.trim();
     final preview = url.isEmpty ? null : _previews[url];
     final loading = url.isNotEmpty && !_previews.containsKey(url);
@@ -312,11 +316,11 @@ class _LibraryLinkSourceState extends State<LibraryLinkSource> {
     );
     final button = FilledButton.icon(
       key: const ValueKey('link-put-up'),
-      onPressed: url.isEmpty || _busy || hint != null ? null : _go,
+      onPressed: url.isEmpty || _busy ? null : _go,
       icon: _busy
           ? const SizedBox.square(dimension: 16, child: CircularProgressIndicator(strokeWidth: 2))
           : const Icon(Icons.play_arrow),
-      label: Text(hint == null ? 'Put it up' : 'Play'),
+      label: Text(solo ? 'Play' : 'Put it up'),
       style: FilledButton.styleFrom(
         minimumSize: const Size(0, 56),
         shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
@@ -361,10 +365,10 @@ class _LibraryLinkSourceState extends State<LibraryLinkSource> {
                       ])
                     : Row(children: [Expanded(child: field), const SizedBox(width: 12), button]),
               ),
-              if (hint != null || _error != null) ...[
+              if (solo || _error != null) ...[
                 const SizedBox(height: 8),
                 Text(
-                  _error ?? hint!,
+                  _error ?? soloPlayHint,
                   key: const ValueKey('link-hint'),
                   textAlign: TextAlign.center,
                   style: t.bodySmall?.copyWith(color: _error != null ? scheme.error : Colors.grey),
@@ -380,7 +384,7 @@ class _LibraryLinkSourceState extends State<LibraryLinkSource> {
                         child: _PreviewCard(preview: preview, loading: loading),
                       ),
               ),
-              if (hint == null) ...[
+              if (!solo) ...[
                 const SizedBox(height: 28),
                 Text('How the others get it', style: t.titleSmall),
                 const SizedBox(height: 10),

apps/desktop/lib/src/shell/library_tab.dart

@@ -16,6 +16,7 @@ import '../screens/home/media_picker.dart';
 import '../state/session_state.dart';
 import 'library_link.dart';
 import 'motion.dart';
+import 'welcome.dart';
 
 /// What putting up a Jellyfin pick sends: its ref (no URL, no token).
 /// Throws [FormatException] with a user-facing message when the server is
@@ -58,9 +59,6 @@ String? nowPlayingFile(Map<String, Object?>? media, String lastPath) {
   return name == media['name'] ? lastPath : null;
 }
 
-/// Offline, nothing goes up; this says why.
-const offlinePutUpHint = 'Join or host to watch together';
-
 /// Window width under which the details panel floats over the library.
 const detailsDockFrom = 1000.0;
 
@@ -68,12 +66,13 @@ const detailsDockFrom = 1000.0;
 /// through), the Jellyfin library chips beside it, and the source below.
 /// Jellyfin cards select on click and open their details in a panel at
 /// the right (docked from [detailsDockFrom], floating over the library
-/// below it); a double-click or the panel's button puts it up. Offline
-/// everything browses and the play buttons say [offlinePutUpHint].
+/// below it); a double-click or the panel's button puts it up. With
+/// nobody else watching ([solo]: offline or a solo session) the buttons
+/// say Play and putting something up starts (or uses) a solo session.
 class LibraryTab extends StatefulWidget {
   final MediaPickerController controller;
   final JellyfinAccounts accounts;
-  final bool online;
+  final bool solo;
   /// This app hosts the server: its files stream from here directly.
   final bool isHost;
   final BrowseStart? jellyfinStart;
@@ -85,15 +84,17 @@ class LibraryTab extends StatefulWidget {
   final RecentLinks? recentLinks;
   final LinkProber probe;
   /// The Files source (tests inject one); defaults to [FilesPage].
-  final Widget Function(BuildContext context, {required bool online, required bool relayed,
+  final Widget Function(BuildContext context, {required bool solo, required bool relayed,
       required Future<String?> Function(String path) onPlay, String? nowPlayingPath})? filesBuilder;
   /// Clock for the Jellyfin Continue row (tests pin it).
   final DateTime Function() now;
+  /// Over the source switch (the shell's welcome band while offline).
+  final Widget? banner;
   const LibraryTab({
     super.key,
     required this.controller,
     required this.accounts,
-    required this.online,
+    required this.solo,
     required this.isHost,
     required this.onPutUp,
     this.onPutUpDone,
@@ -103,6 +104,7 @@ class LibraryTab extends StatefulWidget {
     this.probe = defaultLinkProber,
     this.filesBuilder,
     this.now = DateTime.now,
+    this.banner,
   });
 
   @override
@@ -115,7 +117,6 @@ class _LibraryTabState extends State<LibraryTab> {
   JellyfinSelection? _shown;
 
   MediaPickerController get _c => widget.controller;
-  String? get _hint => widget.online ? null : offlinePutUpHint;
 
   @override
   void initState() {
@@ -163,7 +164,6 @@ class _LibraryTabState extends State<LibraryTab> {
 
   /// A Jellyfin card or episode: a series goes up as its next episode.
   Future<String?> _putUpJellyfin(JellyfinSelection sel) async {
-    if (!widget.online) return offlinePutUpHint;
     final account = widget.accounts.account(sel.serverId);
     final client = widget.accounts.clientFor(sel.serverId);
     if (account == null || client == null) return 'that Jellyfin server is not linked any more';
@@ -181,7 +181,6 @@ class _LibraryTabState extends State<LibraryTab> {
   /// Double-click on a card: put it up, errors as a snack bar.
   Future<void> _doublePutUp(JellyfinSelection sel) async {
     _c.select(sel);
-    if (!widget.online) return;
     final error = await _putUpJellyfin(sel);
     if (error != null && mounted) {
       ScaffoldMessenger.maybeOf(context)?.showSnackBar(SnackBar(content: Text(error)));
@@ -239,11 +238,16 @@ class _LibraryTabState extends State<LibraryTab> {
             onOpenIntegrations: widget.onOpenIntegrations,
             start: widget.jellyfinStart,
             libraryStrip: false,
+            empty: (context) => NoJellyfinPanel(
+              accounts: widget.accounts,
+              onFiles: () => _c.source = MediaKind.file,
+              onLink: () => _c.source = MediaKind.link,
+            ),
           ),
         ),
       MediaKind.link => LibraryLinkSource(
           controller: _c,
-          offlineHint: _hint,
+          solo: widget.solo,
           recents: widget.recentLinks ?? RecentLinks.instance,
           probe: widget.probe,
           onPutUp: _put,
@@ -253,6 +257,15 @@ class _LibraryTabState extends State<LibraryTab> {
 
     final main = Column(
       children: [
+        AnimatedSize(
+          duration: easeTime,
+          curve: ease,
+          alignment: Alignment.topCenter,
+          child: AnimatedSwitcher(
+            duration: easeTime,
+            child: widget.banner ?? const SizedBox(width: double.infinity),
+          ),
+        ),
         header,
         Expanded(child: fadeThrough(KeyedSubtree(key: ValueKey(source), child: content))),
       ],
@@ -267,7 +280,7 @@ class _LibraryTabState extends State<LibraryTab> {
             child: JellyfinDetailsPanel(
               controller: _browse,
               selection: shown,
-              offlineHint: _hint,
+              solo: widget.solo,
               onPutUp: _putUpJellyfin,
               onClose: () => _c.select(null),
             ),
@@ -328,14 +341,14 @@ class _LibraryTabState extends State<LibraryTab> {
     Future<String?> play(String path) => _put(FileMedia(path));
     return SignalBuilder(builder: (context) {
       final session = SessionState.instance;
-      final now = widget.online
+      final now = session.route.value == AppRoute.session
           ? nowPlayingFile(session.coordinator.serverState.value?.media, session.lastForm.mediaPath)
           : null;
       final b = widget.filesBuilder;
       if (b != null) {
-        return b(context, online: widget.online, relayed: relayed, onPlay: play, nowPlayingPath: now);
+        return b(context, solo: widget.solo, relayed: relayed, onPlay: play, nowPlayingPath: now);
       }
-      return FilesPage(online: widget.online, relayed: relayed, onPlay: play, nowPlayingPath: now);
+      return FilesPage(solo: widget.solo, relayed: relayed, onPlay: play, nowPlayingPath: now);
     });
   }
 }

apps/desktop/lib/src/shell/party_strip.dart

@@ -39,8 +39,9 @@ bool viaHostOf(MemberView m, JellyfinRef? ref) =>
     ref != null && m.jf[ref.serverId] == false;
 
 /// The 60 px strip over everything: your avatar (profile), the tabs, and
-/// the party: offline Join / Host, online the avatars (members card),
-/// server and readiness, chat and Leave. Empty space drags the window.
+/// the party: offline Join a friend / Host, solo a "Solo" chip, Invite
+/// friends and Stop, online the avatars (members card), server and
+/// readiness, chat and Leave. Empty space drags the window.
 class PartyStrip extends StatelessWidget {
   final ShellTab tab;
   final ValueChanged<ShellTab> onTab;
@@ -51,6 +52,8 @@ class PartyStrip extends StatelessWidget {
   final VoidCallback onHost;
   final VoidCallback onLeave;
   final VoidCallback onProfile;
+  /// Solo: host from here, keeping what plays.
+  final VoidCallback? onInvite;
 
   /// Online with something up but the player closed: brings it back.
   final VoidCallback? onShowPlayer;
@@ -69,6 +72,7 @@ class PartyStrip extends StatelessWidget {
     required this.onHost,
     required this.onLeave,
     required this.onProfile,
+    this.onInvite,
     this.onShowPlayer,
     this.updates,
     this.windowControls = true,
@@ -83,6 +87,7 @@ class PartyStrip extends StatelessWidget {
         final session = SessionState.instance;
         final coord = session.coordinator;
         final online = session.route.value == AppRoute.session;
+        final solo = online && (session.solo.value || session.switching.value);
         final self = online ? coord.selfMember.value : null;
         return Row(
           children: [
@@ -97,7 +102,7 @@ class PartyStrip extends StatelessWidget {
                 child: StatusAvatar(
                   info: selfAvatarInfo(
                     ready: self?.ready ?? false,
-                    host: online && coord.hostFile != null,
+                    host: online && !solo && coord.hostFile != null,
                   ),
                   size: stripAvatarSize,
                   ring: online,
@@ -130,14 +135,36 @@ class PartyStrip extends StatelessWidget {
             ),
             UpdateIndicator(controller: updates),
             const SizedBox(width: 8),
-            if (online) ...[
-              if (onShowPlayer != null)
+            if (online && onShowPlayer != null)
               IconButton(
                 key: const ValueKey('show-player'),
                 tooltip: 'Show the player',
                 onPressed: onShowPlayer,
                 icon: const Icon(Icons.smart_display_outlined, size: 20),
               ),
+            if (solo) ...[
+              _SoloChip(compact: compact, busy: session.switching.value),
+              const SizedBox(width: 10),
+              if (compact)
+                FilledButton(
+                  key: const ValueKey('strip-invite'),
+                  onPressed: session.switching.value ? null : onInvite,
+                  child: const Text('Invite'),
+                )
+              else
+                FilledButton.icon(
+                  key: const ValueKey('strip-invite'),
+                  onPressed: session.switching.value ? null : onInvite,
+                  icon: const Icon(Icons.group_add_outlined, size: 18),
+                  label: const Text('Invite friends'),
+                ),
+              const SizedBox(width: 8),
+              OutlinedButton(
+                key: const ValueKey('strip-leave'),
+                onPressed: session.switching.value ? null : onLeave,
+                child: const Text('Stop'),
+              ),
+            ] else if (online) ...[
               PartyWatch(
                 builder: (context) => AvatarStack(
                   key: const ValueKey('party-avatars'),
@@ -177,24 +204,36 @@ class PartyStrip extends StatelessWidget {
                 child: const Text('Leave'),
               ),
             ] else ...[
-              if (!compact)
-                Text(
-                  'Offline',
-                  style: TextStyle(color: scheme.onSurfaceVariant),
+              if (!compact) ...[
+                Container(
+                  width: 7,
+                  height: 7,
+                  decoration: BoxDecoration(color: scheme.outline, shape: BoxShape.circle),
                 ),
+                const SizedBox(width: 6),
+                Text('Offline', style: TextStyle(color: scheme.onSurfaceVariant)),
                 const SizedBox(width: 12),
-              FilledButton.tonal(
+              ],
+              if (compact) ...[
+                FilledButton(key: const ValueKey('strip-join'), onPressed: onJoin, child: const Text('Join')),
+                const SizedBox(width: 8),
+                FilledButton.tonal(key: const ValueKey('strip-host'), onPressed: onHost, child: const Text('Host')),
+              ] else ...[
+                FilledButton.icon(
                   key: const ValueKey('strip-join'),
                   onPressed: onJoin,
-                child: const Text('Join'),
+                  icon: const Icon(Icons.login_rounded, size: 18),
+                  label: const Text('Join a friend'),
                 ),
                 const SizedBox(width: 8),
-              FilledButton(
+                FilledButton.tonalIcon(
                   key: const ValueKey('strip-host'),
                   onPressed: onHost,
-                child: const Text('Host'),
+                  icon: const Icon(Icons.podcasts_rounded, size: 18),
+                  label: const Text('Host'),
                 ),
               ],
+            ],
             const SizedBox(width: 8),
             if (windowControls) ...[
               SizedBox(
@@ -270,13 +309,54 @@ class _ServerLabel extends StatelessWidget {
   );
 }
 
-/// "Your server" when hosting, else the address joined.
+/// "Solo" alone, "Your server" when hosting, else the address joined.
 String serverName() {
   final session = SessionState.instance;
+  if (session.solo.peek()) return 'Solo';
   if (session.coordinator.hostFile != null) return 'Your server';
   return session.lastForm.host;
 }
 
+/// Solo: just you, on your own; a spinner while it becomes a server.
+class _SoloChip extends StatelessWidget {
+  final bool compact;
+  final bool busy;
+  const _SoloChip({required this.compact, required this.busy});
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+    return Tooltip(
+      message: busy
+          ? 'Starting your server…'
+          : 'Watching on your own. Nobody can join until you invite friends.',
+      child: Container(
+        key: const ValueKey('solo-chip'),
+        padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+        decoration: BoxDecoration(
+          color: scheme.surfaceContainerHigh,
+          borderRadius: BorderRadius.circular(20),
+        ),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            if (busy)
+              const SizedBox.square(dimension: 14, child: CircularProgressIndicator(strokeWidth: 2))
+            else
+              Icon(Icons.person_outline_rounded, size: 16, color: scheme.primary),
+            const SizedBox(width: 6),
+            Text(busy ? 'Inviting…' : 'Solo', style: const TextStyle(fontWeight: FontWeight.w600)),
+            if (!compact && !busy) ...[
+              const SizedBox(width: 6),
+              Text('only you', style: TextStyle(color: scheme.onSurfaceVariant, fontSize: 12)),
+            ],
+          ],
+        ),
+      ),
+    );
+  }
+}
+
 /// One strip tab: label and an underline that grows in when selected.
 class StripTab extends StatelessWidget {
   final String label;

apps/desktop/lib/src/shell/profile_card.dart

@@ -78,7 +78,7 @@ class _ProfileCardState extends State<ProfileCard> {
           final coord = session.coordinator;
           final online = session.route.value == AppRoute.session;
           final self = online ? coord.selfMember.value : null;
-          final hosting = online && coord.hostFile != null;
+          final hosting = online && !session.solo.value && coord.hostFile != null;
           final color = _p.color.value;
           final png = _p.picture.value;
           final out = self?.out ?? false;

apps/desktop/lib/src/shell/welcome.dart

@@ -0,0 +1,332 @@
+import 'package:flutter/material.dart';
+
+import '../jellyfin/accounts.dart';
+import '../jellyfin/sign_in_panel.dart';
+import '../screens/home/ui.dart' show appName;
+import 'motion.dart';
+
+/// One line under the app name.
+const appTagline = 'Watch together, in sync';
+
+/// Window width from which the welcome band puts the three ways beside
+/// the app name (else under it).
+const welcomeWideFrom = 980.0;
+
+/// Top of the Library while not in a server: the app's name and the three
+/// ways in, Join a friend first (what most people came for), then Host and
+/// Watch solo. None of them needs Jellyfin.
+class WelcomeBand extends StatelessWidget {
+  final VoidCallback onJoin;
+  final VoidCallback onHost;
+  final VoidCallback onSolo;
+  const WelcomeBand({super.key, required this.onJoin, required this.onHost, required this.onSolo});
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+    final t = Theme.of(context).textTheme;
+    final hero = Row(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        ClipRRect(
+          borderRadius: BorderRadius.circular(14),
+          child: Image.asset('assets/icon/icon_256.png', width: 52, height: 52, filterQuality: FilterQuality.medium),
+        ),
+        const SizedBox(width: 14),
+        Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(appName, style: t.titleLarge?.copyWith(fontWeight: FontWeight.w700, height: 1.1)),
+            const SizedBox(height: 2),
+            Text(appTagline, style: TextStyle(color: scheme.onSurfaceVariant)),
+          ],
+        ),
+      ],
+    );
+    final ways = [
+      WayCard(
+        key: const ValueKey('way-join'),
+        icon: Icons.login_rounded,
+        title: 'Join a friend',
+        caption: 'Got an address from a friend? Join with it. Nothing to set up.',
+        primary: true,
+        onTap: onJoin,
+      ),
+      WayCard(
+        key: const ValueKey('way-host'),
+        icon: Icons.podcasts_rounded,
+        title: 'Host',
+        caption: 'You have the video. Friends join you and watch it with you.',
+        onTap: onHost,
+      ),
+      WayCard(
+        key: const ValueKey('way-solo'),
+        icon: Icons.person_outline_rounded,
+        title: 'Watch solo',
+        caption: 'Just you: play anything below. Invite friends any time.',
+        onTap: onSolo,
+      ),
+    ];
+    Widget row(List<Widget> cards) => IntrinsicHeight(
+          child: Row(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              for (final (i, c) in cards.indexed) ...[if (i > 0) const SizedBox(width: 10), Expanded(child: c)],
+            ],
+          ),
+        );
+    return Container(
+      key: const ValueKey('welcome-band'),
+      margin: const EdgeInsets.fromLTRB(20, 16, 20, 0),
+      padding: const EdgeInsets.all(14),
+      decoration: BoxDecoration(
+        borderRadius: BorderRadius.circular(18),
+        gradient: LinearGradient(
+          begin: Alignment.topLeft,
+          end: Alignment.bottomRight,
+          colors: [scheme.primary.withValues(alpha: 0.16), scheme.primary.withValues(alpha: 0.03)],
+        ),
+        border: Border.all(color: scheme.outlineVariant.withValues(alpha: 0.4)),
+      ),
+      child: LayoutBuilder(builder: (context, box) {
+        if (box.maxWidth >= welcomeWideFrom - 40) {
+          return Row(
+            children: [
+              Padding(padding: const EdgeInsets.only(left: 4, right: 20), child: hero),
+              Expanded(child: row(ways)),
+            ],
+          );
+        }
+        return Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Padding(padding: const EdgeInsets.only(left: 4, bottom: 12), child: hero),
+            if (box.maxWidth >= 520)
+              row(ways)
+            else
+              for (final (i, c) in ways.indexed) ...[if (i > 0) const SizedBox(height: 8), c],
+          ],
+        );
+      }),
+    );
+  }
+}
+
+/// One way in: a tinted icon, a title and a one-line caption.
+class WayCard extends StatefulWidget {
+  final IconData icon;
+  final String title;
+  final String caption;
+  final bool primary;
+  final VoidCallback onTap;
+  const WayCard({
+    super.key,
+    required this.icon,
+    required this.title,
+    required this.caption,
+    required this.onTap,
+    this.primary = false,
+  });
+
+  @override
+  State<WayCard> createState() => _WayCardState();
+}
+
+class _WayCardState extends State<WayCard> {
+  bool _hover = false;
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+    final primary = widget.primary;
+    final bg = primary ? scheme.primaryContainer : scheme.surfaceContainerHigh;
+    final fg = primary ? scheme.onPrimaryContainer : scheme.onSurface;
+    return MouseRegion(
+      onEnter: (_) => setState(() => _hover = true),
+      onExit: (_) => setState(() => _hover = false),
+      child: AnimatedScale(
+        duration: easeTime,
+        curve: ease,
+        scale: _hover ? 1.015 : 1,
+        child: Material(
+          color: bg,
+          borderRadius: BorderRadius.circular(14),
+          clipBehavior: Clip.antiAlias,
+          child: InkWell(
+            onTap: widget.onTap,
+            child: Padding(
+              padding: const EdgeInsets.fromLTRB(12, 12, 14, 12),
+              child: Row(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Container(
+                    width: 36,
+                    height: 36,
+                    decoration: BoxDecoration(
+                      color: primary ? scheme.primary : scheme.primary.withValues(alpha: 0.14),
+                      borderRadius: BorderRadius.circular(10),
+                    ),
+                    child: Icon(widget.icon, size: 20, color: primary ? scheme.onPrimary : scheme.primary),
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Text(widget.title, style: TextStyle(fontWeight: FontWeight.w700, color: fg)),
+                        const SizedBox(height: 2),
+                        Text(widget.caption,
+                            maxLines: 2,
+                            overflow: TextOverflow.ellipsis,
+                            style: TextStyle(fontSize: 12, height: 1.3, color: fg.withValues(alpha: 0.72))),
+                      ],
+                    ),
+                  ),
+                ],
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+/// The Library's Jellyfin source with no server linked: what plays with
+/// nothing set up (Files, Link), then Jellyfin as an optional extra that
+/// guests never need. The sign-in opens in place.
+class NoJellyfinPanel extends StatefulWidget {
+  final JellyfinAccounts accounts;
+  final VoidCallback onFiles;
+  final VoidCallback onLink;
+  const NoJellyfinPanel({super.key, required this.accounts, required this.onFiles, required this.onLink});
+
+  @override
+  State<NoJellyfinPanel> createState() => _NoJellyfinPanelState();
+}
+
+class _NoJellyfinPanelState extends State<NoJellyfinPanel> {
+  bool _signIn = false;
+
+  @override
+  Widget build(BuildContext context) {
+    final scheme = Theme.of(context).colorScheme;
+    final t = Theme.of(context).textTheme;
+    final muted = TextStyle(color: scheme.onSurfaceVariant);
+    final sources = [
+      WayCard(
+        key: const ValueKey('source-files'),
+        icon: Icons.folder_outlined,
+        title: 'Files',
+        caption: 'Videos on this computer. Drop a file or folder anywhere.',
+        onTap: widget.onFiles,
+      ),
+      WayCard(
+        key: const ValueKey('source-link'),
+        icon: Icons.link,
+        title: 'Link',
+        caption: 'YouTube, X, or any video address. Ctrl+V anywhere.',
+        onTap: widget.onLink,
+      ),
+    ];
+    return SingleChildScrollView(
+      key: const ValueKey('media-jellyfin'),
+      padding: const EdgeInsets.only(bottom: 24),
+      child: Align(
+        alignment: Alignment.topLeft,
+        child: ConstrainedBox(
+          constraints: const BoxConstraints(maxWidth: 640),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              Text('Pick something to watch', style: t.titleMedium),
+              const SizedBox(height: 4),
+              Text('No account needed: these work for everyone.', style: muted),
+              const SizedBox(height: 12),
+              LayoutBuilder(
+                builder: (context, box) => box.maxWidth < 460
+                    ? Column(children: [sources[0], const SizedBox(height: 8), sources[1]])
+                    : IntrinsicHeight(
+                        child: Row(
+                          crossAxisAlignment: CrossAxisAlignment.stretch,
+                          children: [
+                            Expanded(child: sources[0]),
+                            const SizedBox(width: 10),
+                            Expanded(child: sources[1]),
+                          ],
+                        ),
+                      ),
+              ),
+              const SizedBox(height: 20),
+              Material(
+                key: const ValueKey('jellyfin-optional'),
+                color: scheme.surfaceContainer,
+                shape: RoundedRectangleBorder(
+                  borderRadius: BorderRadius.circular(14),
+                  side: BorderSide(color: scheme.outlineVariant.withValues(alpha: 0.5)),
+                ),
+                clipBehavior: Clip.antiAlias,
+                child: AnimatedSize(
+                  duration: easeTime,
+                  curve: ease,
+                  alignment: Alignment.topCenter,
+                  child: Padding(
+                    padding: const EdgeInsets.all(16),
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.stretch,
+                      children: [
+                        Row(
+                          children: [
+                            Icon(Icons.video_library_outlined, color: scheme.onSurfaceVariant),
+                            const SizedBox(width: 12),
+                            Expanded(
+                              child: Column(
+                                crossAxisAlignment: CrossAxisAlignment.start,
+                                children: [
+                                  Wrap(spacing: 8, crossAxisAlignment: WrapCrossAlignment.center, children: [
+                                    const Text('Jellyfin', style: TextStyle(fontWeight: FontWeight.w600)),
+                                    Container(
+                                      padding: const EdgeInsets.symmetric(horizontal: 7, vertical: 1),
+                                      decoration: BoxDecoration(
+                                        color: scheme.surfaceContainerHighest,
+                                        borderRadius: BorderRadius.circular(6),
+                                      ),
+                                      child: Text('optional', style: TextStyle(fontSize: 11, color: scheme.onSurfaceVariant)),
+                                    ),
+                                  ]),
+                                  Text(
+                                    'Only if you have a Jellyfin server: browse it here, '
+                                    'with progress and next episodes. Joining a friend never needs it.',
+                                    style: muted.copyWith(fontSize: 12),
+                                  ),
+                                ],
+                              ),
+                            ),
+                          ],
+                        ),
+                        if (!_signIn)
+                          Align(
+                            alignment: Alignment.centerRight,
+                            child: TextButton(
+                              key: const ValueKey('jellyfin-link'),
+                              onPressed: () => setState(() => _signIn = true),
+                              child: const Text('Link a server'),
+                            ),
+                          ),
+                        if (_signIn) ...[
+                          const SizedBox(height: 14),
+                          JellyfinSignInPanel(accounts: widget.accounts, onCancel: () => setState(() => _signIn = false)),
+                        ],
+                      ],
+                    ),
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

apps/desktop/lib/src/state/server_isolate.dart

@@ -33,8 +33,10 @@ class ServerIsolate {
 
   /// Spawns the server and waits until it listens. Throws a
   /// [StateError] with the server's message if it cannot start.
+  /// [loopbackOnly]: 127.0.0.1 only (the solo session).
   static Future<ServerIsolate> start(
     AppConfig config, {
+    bool loopbackOnly = false,
     required void Function(String line) onLog,
     required void Function(String error) onCrash,
     Duration timeout = const Duration(seconds: 15),
@@ -83,7 +85,7 @@ class ServerIsolate {
     final Isolate isolate;
     try {
       isolate = await Isolate.spawn(
-          _serverMain, (config.toMap(), events.sendPort),
+          _serverMain, ({...config.toMap(), if (loopbackOnly) 'loopbackOnly': true}, events.sendPort),
           errorsAreFatal: false,
           onError: errors.sendPort,
           onExit: exit.sendPort,

apps/desktop/lib/src/state/session_state.dart

@@ -8,6 +8,7 @@ import 'package:sync_relay_core/core.dart';
 
 import '../jellyfin/accounts.dart';
 import '../jellyfin/session_media.dart';
+import '../screens/home/picked_media.dart';
 import '../playback/yt_dlp_app.dart';
 import '../sfx/sfx.dart';
 import '../sfx/sound_bank.dart';
@@ -169,6 +170,13 @@ class SessionState {
   /// Set when the hosted server died mid-session; Home shows it on the
   /// Host card and clears it.
   final serverCrash = signal<String?>(null);
+  /// In a solo session: this app's own server on 127.0.0.1, only you in
+  /// it. Hosting from it ([host]) keeps what plays and where.
+  final solo = signal(false);
+  /// A solo session is becoming a hosted one: the player has nothing open
+  /// until the media is up again on the new server.
+  final switching = signal(false);
+  ConnectParams? _soloParams;
 
   /// The app's yt-dlp folder for the hosted server; '' (the server's own
   /// default) when the app-support folder is not available.
@@ -243,9 +251,80 @@ class SessionState {
     await _saveFormQuietly();
   }
 
+  /// Hosts a server friends can join. From a solo session it keeps the
+  /// media and position: the solo server goes, the new one gets the same
+  /// pick, seeked to where it was; if hosting fails, solo comes back.
   Future<void> host(ConnectParams params, ConnectForm form) async {
+    if (!solo.peek()) return _host(params, form: form);
+    final carry = _carry();
+    switching.value = true;
+    try {
+      await coordinator.leave();
+      await stopServer();
+      solo.value = false;
+      try {
+        await _host(params, form: form);
+      } catch (_) {
+        // Not hosted (failed or cancelled): back to solo, same media.
+        try {
+          await _host(_soloParams ?? params, soloSession: true);
+          if (carry != null) await _resume(carry);
+        } catch (e) {
+          debugPrint('back to solo failed: $e');
+          await leave();
+        }
+        rethrow;
+      }
+      try {
+        if (carry != null) await _resume(carry);
+      } catch (e) {
+        coordinator.showToast("couldn't put it up again: $e");
+      }
+    } finally {
+      switching.value = false;
+    }
+  }
+
+  /// Watch alone: the same hosted path, on 127.0.0.1 and a free port, no
+  /// password, nothing put up yet. Nobody else can reach it.
+  Future<void> startSolo(ConnectParams params) async {
+    if (route.peek() == AppRoute.session) return;
+    _soloParams = params;
+    await _host(params, soloSession: true);
+  }
+
+  ({PickedMedia pick, double position})? _carry() {
+    final pick = coordinator.lastPick;
+    if (pick == null || coordinator.serverState.peek()?.media == null) return null;
+    final pos = coordinator.playback.positionSecs;
+    return (pick: pick, position: pos.isFinite && pos > 0 ? pos : 0.0);
+  }
+
+  /// Puts [carry] up on the server just joined and seeks to its position
+  /// once the swap shows in a state.
+  Future<void> _resume(({PickedMedia pick, double position}) carry) async {
+    final before = coordinator.serverState.peek()?.mediaId ?? 0;
+    final error = await coordinator.swapPicked(carry.pick);
+    if (error != null) throw StateError(error);
+    if (carry.position < 1) return;
+    final landed = Completer<void>();
+    final stop = effect(() {
+      final r = coordinator.serverState.value;
+      if (r != null && r.media != null && r.mediaId > before && !landed.isCompleted) landed.complete();
+    });
+    try {
+      await landed.future.timeout(const Duration(seconds: 20));
+      coordinator.sync.sendSeek(carry.position);
+    } on TimeoutException {
+      debugPrint('resume: the media did not come up; not seeking');
+    } finally {
+      stop();
+    }
+  }
+
+  Future<void> _host(ConnectParams params, {ConnectForm? form, bool soloSession = false}) async {
     final op = ++_op;
-    _rememberForm(form);
+    if (form != null) _rememberForm(form);
     try {
       status.value =
           const HealthStatus(HealthSeverity.info, 'starting server…');
@@ -265,14 +344,15 @@ class SessionState {
       try {
         server = await ServerIsolate.start(
           AppConfig(
-            port: params.port,
-            secret: params.secret,
+            port: soloSession ? 0 : params.port,
+            secret: soloSession ? '' : params.secret,
             name: 'server',
             mediaPath: params.mediaPath,
             hostKey: hostKey,
             jellyfin: relay,
             ytDlpDir: await _sharedYtDlpDir(),
           ),
+          loopbackOnly: soloSession,
           onLog: (line) => debugPrint('[server] $line'),
           onCrash: (cause) => _onServerCrash(server, cause),
         );
@@ -289,13 +369,13 @@ class SessionState {
       _server = server;
       coordinator.hostFile = (path) async =>
           identical(_server, server) ? server.setFile(path) : null;
-      status.value =
-          HealthStatus(HealthSeverity.ok, 'hosting on port ${server.port}');
+      status.value = HealthStatus(
+          HealthSeverity.ok, soloSession ? 'watching solo' : 'hosting on port ${server.port}');
       try {
         await coordinator.connect(ConnectParams(
           host: '127.0.0.1',
           port: server.port,
-          secret: params.secret,
+          secret: soloSession ? '' : params.secret,
           name: params.name,
           avatar: params.avatar,
           hostKey: hostKey,
@@ -309,9 +389,10 @@ class SessionState {
         if (crash != null && e is! ConnectCancelled) throw ServerCrashed(crash);
         rethrow;
       }
+      solo.value = soloSession;
       route.value = AppRoute.session;
     } finally {
-      await _saveFormQuietly();
+      if (form != null) await _saveFormQuietly();
     }
   }
 
@@ -349,7 +430,9 @@ class SessionState {
     try {
       await coordinator.cancelConnect();
     } catch (_) {}
-    await stopServer();
+    // Solo becoming hosted: [host] stops what it started and goes back
+    // to solo itself.
+    if (!switching.peek()) await stopServer();
   }
 
   /// Saved whatever the outcome: a failed join is exactly when the user
@@ -385,6 +468,7 @@ class SessionState {
   Future<void> leave() async {
     await coordinator.leave();
     await stopServer();
+    solo.value = false;
     status.value = const HealthStatus(HealthSeverity.info, 'idle');
     route.value = AppRoute.home;
   }

apps/desktop/test/files_page_test.dart

@@ -44,7 +44,7 @@ Future<void> frames(WidgetTester tester, [int n = 10]) async {
 Future<void> pumpPage(
   WidgetTester tester, {
   Size size = const Size(1280, 800),
-  bool online = true,
+  bool solo = false,
   bool relayed = false,
   Future<String?> Function(String path)? onPlay,
   ThumbnailLoader? thumbnails,
@@ -56,7 +56,7 @@ Future<void> pumpPage(
   await tester.pumpWidget(MaterialApp(
     home: Scaffold(
       body: FilesPage(
-        online: online,
+        solo: solo,
         relayed: relayed,
         onPlay: onPlay ?? (_) async => null,
         thumbnails: thumbnails ?? fakeThumb,
@@ -206,24 +206,6 @@ void main() {
     expect(find.text('4 episodes · 1 extra · Grp'), findsOneWidget);
   });
 
-  testWidgets('offline: browsing works, playing is disabled', (tester) async {
-    store.addFolder(anime);
-    final played = <String>[];
-    await pumpPage(tester, online: false, onPlay: (p) async {
-      played.add(p);
-      return null;
-    });
-    await openFolder(tester, 'anime');
-    await openSeries(tester);
-    expect(find.text('E01'), findsOneWidget);
-    await tester.tap(find.text('E01'));
-    await tester.tap(find.text('Some Movie (2019)'));
-    await frames(tester);
-    expect(played, isEmpty);
-    expect(store.recent.value, isEmpty);
-    expect(find.byTooltip(offlinePlayHint), findsWidgets);
-  });
-
   testWidgets('a play goes to onPlay and into Recent', (tester) async {
     store.addFolder(anime);
     final played = <String>[];
@@ -261,7 +243,6 @@ void main() {
     await tester.pumpWidget(MaterialApp(
       home: Scaffold(
         body: FilesPage(
-          online: true,
           relayed: false,
           onPlay: (_) async => null,
           nowPlayingPath: '$anime/[Grp] Show - 03.mkv',

apps/desktop/test/home_test.dart

@@ -8,6 +8,7 @@ import 'package:sync_relay_core/core.dart';
 import 'package:watch_together/src/screens/home/health_probe.dart';
 import 'package:watch_together/src/screens/home/media_picker.dart';
 import 'package:watch_together/src/shell/app_shell.dart';
+import 'package:watch_together/src/shell/library_link.dart' show soloPlayHint;
 import 'package:watch_together/src/state/session_state.dart';
 import 'package:watch_together/src/state/settings.dart';
 import 'package:watch_together/src/update/update_controller.dart';
@@ -230,24 +231,28 @@ void main() {
     expect(find.byKey(const ValueKey('join-row')), findsOneWidget);
   });
 
-  testWidgets('library: sources switch; offline nothing goes up; Integrations opens Settings', (tester) async {
+  testWidgets('library offline: welcome band, sources that need nothing, Jellyfin optional', (tester) async {
     await pumpShell(tester, const Size(1280, 900));
-    await tester.tap(find.text('Files'));
+    // The three ways in, Join first; none needs Jellyfin.
+    expect(find.byKey(const ValueKey('welcome-band')), findsOneWidget);
+    expect(find.text('Watch together, in sync'), findsOneWidget);
+    final join = tester.getTopLeft(find.byKey(const ValueKey('way-join')));
+    expect(join.dx, lessThan(tester.getTopLeft(find.byKey(const ValueKey('way-solo'))).dx));
+    // No linked server: Files and Link first, Jellyfin as an optional card.
+    expect(find.text('Pick something to watch'), findsOneWidget);
+    expect(find.text('Add a Jellyfin server'), findsNothing);
+    await tester.tap(find.byKey(const ValueKey('jellyfin-link')));
+    await tester.pumpAndSettle();
+    expect(find.text('Add a Jellyfin server'), findsOneWidget);
+    await tester.tap(find.byKey(const ValueKey('source-files')));
     await tester.pumpAndSettle();
     expect(find.byType(FilesPage), findsOneWidget);
     await tester.tap(find.text('Link'));
     await tester.pumpAndSettle();
     expect(find.text('Watch from a link'), findsOneWidget);
-    // Offline nothing goes up.
-    expect(find.text('Join or host to watch together'), findsOneWidget);
+    // Alone: Play, no relay modes.
+    expect(find.text(soloPlayHint), findsOneWidget);
     expect(find.text('How the others get it'), findsNothing);
-    await tester.tap(find.text('Jellyfin'));
-    await tester.pumpAndSettle();
-    // No linked server: sign-in right in the library.
-    expect(find.text('Add a Jellyfin server'), findsOneWidget);
-    await tester.tap(find.text('Open Integrations'));
-    await tester.pumpAndSettle();
-    expect(find.text('Add server'), findsOneWidget);
     expect(tester.takeException(), isNull);
   });
 

apps/desktop/test/library_tab_test.dart

@@ -48,16 +48,16 @@ FakeJellyfin libraryFake() {
 }
 
 class FilesStub extends StatelessWidget {
-  final bool online, relayed;
+  final bool solo, relayed;
   final Future<String?> Function(String path) onPlay;
-  const FilesStub({super.key, required this.online, required this.relayed, required this.onPlay});
+  const FilesStub({super.key, required this.solo, required this.relayed, required this.onPlay});
 
   @override
   Widget build(BuildContext context) => Column(children: [
-        Text('files online=$online relayed=$relayed'),
+        Text('files solo=$solo relayed=$relayed'),
         TextButton(
           key: const ValueKey('stub-play'),
-          onPressed: online ? () => onPlay('/v/a.mkv') : null,
+          onPressed: () => onPlay('/v/a.mkv'),
           child: const Text('play'),
         ),
       ]);
@@ -75,7 +75,7 @@ class Harness {
 Future<Harness> pumpLibrary(
   WidgetTester tester,
   Size size, {
-  bool online = true,
+  bool solo = false,
   bool isHost = false,
   MediaKind source = MediaKind.jellyfin,
   Harness? reuse,
@@ -103,7 +103,7 @@ Future<Harness> pumpLibrary(
         key: UniqueKey(),
         controller: h.controller,
         accounts: h.accounts,
-        online: online,
+        solo: solo,
         isHost: isHost,
         jellyfinStart: start,
         recentLinks: h.recents,
@@ -111,8 +111,8 @@ Future<Harness> pumpLibrary(
         probe: (url) async => url.endsWith('.mkv')
             ? LinkProbe.file(Uri.parse(url), 1)
             : LinkProbe.page(Uri.parse(url), info: const YtDlpInfo(title: 'A video', uploader: 'Chan')),
-        filesBuilder: (context, {required online, required relayed, required onPlay, nowPlayingPath}) =>
-            FilesStub(online: online, relayed: relayed, onPlay: onPlay),
+        filesBuilder: (context, {required solo, required relayed, required onPlay, nowPlayingPath}) =>
+            FilesStub(solo: solo, relayed: relayed, onPlay: onPlay),
         onPutUp: (m) async {
           h.put.add(m);
           return null;
@@ -152,7 +152,7 @@ void main() {
 
     await tester.tap(find.text('Files'));
     await settle(tester, 10);
-    expect(find.text('files online=true relayed=true'), findsOneWidget);
+    expect(find.text('files solo=false relayed=true'), findsOneWidget);
     await tester.tap(find.byKey(const ValueKey('stub-play')));
     await settle(tester);
     expect(h.put, [const FileMedia('/v/a.mkv')]);
@@ -247,32 +247,26 @@ void main() {
     expect(tester.takeException(), isNull);
   });
 
-  testWidgets('offline: everything browses, nothing goes up', (tester) async {
-    final h = await pumpLibrary(tester, const Size(1600, 1000), online: false);
+  testWidgets('solo: buttons say Play and put up; a link goes direct, no relay modes', (tester) async {
+    final h = await pumpLibrary(tester, const Size(1600, 1000), solo: true);
     await tester.tap(arifuretaCard());
     await settle(tester, 10);
     final go = find.byKey(const ValueKey('details-put-up'));
-    expect(tester.widget<ButtonStyleButton>(go).onPressed, isNull);
-    expect(find.descendant(of: go, matching: find.text('Play')), findsOneWidget);
-    expect(find.text(offlinePutUpHint), findsOneWidget);
-    await doubleTap(tester, arifuretaCard());
-    expect(h.put, isEmpty);
+    expect(find.descendant(of: go, matching: find.textContaining('Play')), findsOneWidget);
+    await tester.tap(go);
+    await settle(tester, 10);
+    expect(h.put.single, isA<JellyfinMedia>());
 
     await tester.tap(find.text('Link'));
     await settle(tester, 10);
+    h.controller.linkRelay = LinkRelay.me;
     await tester.enterText(find.byKey(const ValueKey('link-field')), 'https://cdn.example/a.mkv');
     await settle(tester, 10);
-    final linkGo = find.byKey(const ValueKey('link-put-up'));
-    expect(tester.widget<ButtonStyleButton>(linkGo).onPressed, isNull);
-    expect(find.descendant(of: find.byKey(const ValueKey('media-link')), matching: find.text(offlinePutUpHint)),
-        findsOneWidget);
     expect(find.text('How the others get it'), findsNothing);
-    expect(find.text('a.mkv'), findsOneWidget, reason: 'the preview still works');
-
-    await tester.tap(find.text('Files'));
+    expect(find.text(soloPlayHint), findsOneWidget);
+    await tester.tap(find.byKey(const ValueKey('link-put-up')));
     await settle(tester, 10);
-    expect(find.text('files online=false relayed=true'), findsOneWidget);
-    expect(h.put, isEmpty);
+    expect(h.put.last, const LinkMedia('https://cdn.example/a.mkv'));
     expect(tester.takeException(), isNull);
   });
 
@@ -307,7 +301,7 @@ void main() {
 
   testWidgets('hosting: files stream from here; now-playing file passes through', (tester) async {
     await pumpLibrary(tester, const Size(1400, 900), source: MediaKind.file, isHost: true);
-    expect(find.text('files online=true relayed=false'), findsOneWidget);
+    expect(find.text('files solo=false relayed=false'), findsOneWidget);
   });
 
   testWidgets('the last pick comes back selected; "Change video" opens on its series', (tester) async {
@@ -325,7 +319,7 @@ void main() {
     expect(c.selected!.itemId, bsEpisode);
     expect(c.source, MediaKind.jellyfin);
     final h = Harness(c, accounts, FakeJellyfin());
-    await pumpLibrary(tester, const Size(1600, 1000), reuse: h, online: false);
+    await pumpLibrary(tester, const Size(1600, 1000), reuse: h, solo: true);
     expect(find.byKey(const ValueKey('jf-details')), findsOneWidget);
     expect(find.text('Black Summoner'), findsWidgets);
 

apps/desktop/test/schedule_page_test.dart

@@ -231,7 +231,7 @@ void main() {
     WidgetTester tester, {
     Size size = const Size(2560, 1080),
     ScheduleSnapshot Function()? snap,
-    bool online = true,
+    bool solo = false,
     JellyfinAccounts? accounts,
   }) async {
     toasts.clear();
@@ -245,7 +245,7 @@ void main() {
         theme: ThemeData.dark(),
         home: Scaffold(
           body: SchedulePage(
-            online: online,
+            solo: solo,
             repository: repo,
             accounts: accounts,
             onToast: toasts.add,
@@ -434,11 +434,11 @@ void main() {
     await done(tester);
   });
 
-  testWidgets('offline: Play is disabled', (tester) async {
-    await pumpPage(tester, online: false);
+  testWidgets('solo: the button says Play and works', (tester) async {
+    await pumpPage(tester, solo: true);
     expect(find.text('Put it up'), findsNothing);
     final b = widgetOf<ButtonStyleButton>(tester, action(111, 3));
-    expect(b.onPressed, isNull);
+    expect(b.onPressed, isNotNull);
     expect(find.text('Play'), findsOneWidget);
     await done(tester);
   });

apps/desktop/test/server_isolate_test.dart

@@ -8,6 +8,7 @@ import 'package:hive_ce/hive.dart';
 import 'package:media_kit/media_kit.dart';
 import 'package:sync_relay_core/core.dart';
 import 'package:watch_together/src/jellyfin/accounts.dart';
+import 'package:watch_together/src/screens/home/picked_media.dart';
 import 'package:watch_together/src/session/session_coordinator.dart';
 import 'package:watch_together/src/state/server_isolate.dart';
 import 'package:watch_together/src/state/session_state.dart';
@@ -218,4 +219,45 @@ void main() {
       if (file.existsSync()) file.deleteSync();
     }
   });
+
+  test('solo: loopback-only server; inviting friends hosts the same media',
+      timeout: const Timeout(Duration(minutes: 2)), () async {
+    MediaKit.ensureInitialized();
+    final tmp = Platform.environment['WT_TEST_TMP'] ?? Directory.systemTemp.path;
+    Hive.init('$tmp/hive_isolate_solo_test');
+    final session = SessionState.instance;
+    final port = await _freePort();
+    _Raw? friend;
+    final file = File('$tmp/solo carry.mkv')..writeAsBytesSync(List.filled(4096, 7));
+    session.route.value = AppRoute.home; // the tests above leave it set
+    try {
+      await session.startSolo(const ConnectParams(host: '127.0.0.1', port: 0, secret: '', name: 'me'));
+      expect(session.route.peek(), AppRoute.session);
+      expect(session.solo.peek(), isTrue);
+      await session.coordinator.playback.player.setVolume(0);
+      final soloPort = session.hostedServer!.port;
+      // Reachable on loopback only: a LAN address of this machine is refused.
+      final lan = [
+        for (final i in await NetworkInterface.list(type: InternetAddressType.IPv4))
+          for (final a in i.addresses)
+            if (!a.isLoopback) a,
+      ];
+      if (lan.isNotEmpty) {
+        await expectLater(Socket.connect(lan.first, soloPort, timeout: const Duration(seconds: 3)),
+            throwsA(isA<SocketException>()));
+      }
+      expect(await session.coordinator.swapPicked(FileMedia(file.path)), isNull);
+      await _poll(() => session.coordinator.serverState.peek()?.media?['name'] == 'solo carry.mkv', 'solo media');
+
+      await session.host(ConnectParams(host: '', port: port, secret: 'pw', name: 'me'), ConnectForm());
+      expect(session.solo.peek(), isFalse);
+      expect(session.route.peek(), AppRoute.session);
+      friend = await _Raw.join(port, 'friend', secret: 'pw');
+      await friend.next('state', where: (m) => (m['media'] as Map?)?['name'] == 'solo carry.mkv');
+    } finally {
+      await friend?.ws.close();
+      await session.leave();
+      if (file.existsSync()) file.deleteSync();
+    }
+  });
 }

apps/desktop/test/shell_test.dart

@@ -128,6 +128,29 @@ void main() {
       expect(session.route.value, AppRoute.session);
     });
 
+    testWidgets('solo: just you, Invite friends opens the host card, Stop asks nothing', (tester) async {
+      await pumpShell(tester, const Size(1280, 800));
+      session.solo.value = true;
+      addTearDown(() => session.solo.value = false);
+      online([member('me', 'Me')], media: false);
+      await tester.pumpAndSettle();
+      expect(find.byKey(const ValueKey('solo-chip')), findsOneWidget);
+      expect(find.byKey(const ValueKey('party-avatars')), findsNothing);
+      expect(find.byKey(const ValueKey('strip-chat')), findsNothing);
+      expect(find.byKey(const ValueKey('welcome-band')), findsNothing);
+      await tester.tap(find.byKey(const ValueKey('strip-invite')));
+      await tester.pumpAndSettle();
+      expect(find.text('Invite friends'), findsWidgets);
+      expect(find.text('Start hosting'), findsOneWidget);
+      await tester.tapAt(const Offset(5, 790));
+      await tester.pumpAndSettle();
+      await tester.tap(find.byKey(const ValueKey('strip-leave')));
+      await tester.pumpAndSettle();
+      expect(find.text('Leave server?'), findsNothing);
+      expect(session.route.value, AppRoute.home);
+      expect(session.solo.value, isFalse);
+    });
+
     testWidgets('compact below 1100 px: 3 avatars, no server text', (tester) async {
       await pumpShell(tester, const Size(1000, 800));
       online(party, media: false);

docs/ARCHITECTURE.md

@@ -40,6 +40,23 @@ size (`ServerIsolate.setFile`): the host's in-session File swap then sends a
   shell says so in a dialog (during setup the host attempt fails with it).
   Stop (leave, close, cancel during setup, a failed own join)
   sends `stop`, waits up to 3 s for exit, then kills the isolate.
+- **Solo session** (watching alone): the same hosting path, so nothing
+  about solo is a second code path or on the wire. Putting something up
+  while offline (`AppShellState._putUp`) calls `SessionState.startSolo`:
+  a `ServerIsolate` with `loopbackOnly` (an extra `'loopbackOnly': true`
+  key next to the `AppConfig` map; `SyncServer` binds 127.0.0.1 instead
+  of every IPv4 interface), port 0 (a free one), no password, a host key;
+  the app joins it and `SessionState.solo` is set. Everything a session
+  has works (Jellyfin progress, next episode, skip pills, the player); a
+  link goes up direct (no relay mode). Invite friends opens the Host card,
+  whose submit (`SessionState.host` while solo) remembers the
+  coordinator's `lastPick` (the last `swapLink` / `swapJellyfin` /
+  `swapFile` of this connection) and position, leaves and stops the solo
+  server, hosts on the card's port and password, swaps the same pick and
+  seeks once a state shows it (`switching` is set meanwhile; the shell
+  closes the player and reopens it as it was). If hosting fails or is
+  cancelled, solo starts again with the same media. Stop leaves without
+  asking.
 - **Dedicated server**: `bin/server.dart` compiled with `dart compile exe`
   and shipped next to the app as `watch-together-server`. It parses flags
   (`--port`, `--secret`, `--name`, `--media`, `--advertise-host`,
@@ -673,8 +690,11 @@ always scrolls the page). Space never presses a focused button
 
 - **Party strip** (`party_strip.dart`, 60 px): your avatar (profile card; 42 px like the party's),
   the Library / Schedule / Settings tabs with a growing underline (an
-  `HScroll` when narrow), the update indicator, then offline Join and Host
-  (connect cards), online the party: `AvatarStack` (host first, then
+  `HScroll` when narrow), the update indicator, then offline a grey dot,
+  "Offline", Join a friend and Host (connect cards; icon-less "Join" and
+  "Host" under 1100 px), solo a "Solo · only you" chip, Invite friends
+  (the Host card, titled "Invite friends", "Start hosting") and Stop (no
+  dialog; no avatars or chat), online the party: `AvatarStack` (host first, then
   ready; spreads on hover; 5 shown, 3 under 1100 px), the server name and
   "ready n/m" (hidden under 1100 px), chat with an unread badge, and Leave
   (asks first). The stack opens the members card (status, host / relay
@@ -702,7 +722,8 @@ always scrolls the page). Space never presses a focused button
   to watch is picked in the library afterwards. Submit state (busy,
   cancel, per-card errors) is `ConnectFlow`, owned by the shell so an
   attempt and its error outlive the card; a card closes itself once
-  online.
+  in a server that is not solo. Join says that a friend gives the address
+  and that no account or Jellyfin is needed.
 - **Profile** (`profile_card.dart`, `screens/home/profile.dart`): a card
   tinted with your colour: picture (hover "Change" opens `CropPicker`:
   drag, wheel or slider zoom, previews at 88/42/24 px, exports a 256 px
@@ -711,6 +732,14 @@ always scrolls the page). Space never presses a focused button
   the `connect_form` box (an old picture path is shrunk once and kept as
   bytes). Online, a name change (once typing settles) or picture change
   goes out through `Profile.push` (`coordinator.updateProfile`).
+- **Welcome** (`welcome.dart`): offline the Library opens with
+  `WelcomeBand` over the source switch (sizes away when online): the app
+  icon, Starsync and "Watch together, in sync", then three `WayCard`s,
+  Join a friend first (filled), Host, Watch solo (opens Files, or
+  Jellyfin when linked); beside the name from 940 px, under it below,
+  stacked under 520 px. With no Jellyfin server linked the Jellyfin source
+  is `NoJellyfinPanel`: Files and Link cards ("No account needed") and an
+  optional Jellyfin card whose "Link a server" opens the sign-in in place.
 - **Tabs**: Library (`library_tab.dart`): a source switch (Jellyfin /
   Link / Files, fade through) with the Jellyfin library chips beside it.
   Its state (source, link field and relay mode, selected Jellyfin card,
@@ -730,8 +759,10 @@ always scrolls the page). Space never presses a focused button
   is `FilesPage` (`files/`): watched folders (`FolderStore`) scanned in
   an isolate, videos grouped by series; series start collapsed, a header
   click opens one and open ones stay open for the app session
-  (`showFilesFolder` opens a folder from outside). Offline everything browses; the buttons say "Join or host to
-  watch together". Schedule (`schedule/`) is a week of day columns built
+  (`showFilesFolder` opens a folder from outside). With nobody else
+  watching (`solo` on the Library, Files and Schedule: offline or solo)
+  the buttons say Play, Link has no relay modes and Files no relay notice;
+  offline a put-up starts a solo session. Schedule (`schedule/`) is a week of day columns built
   from AniList's airing schedule (`anilist.dart`: pages cached 10 min in
   memory and 1 h on disk, stale data shown on 429 or failure) matched
   against AnimeFlow (`animeflow.dart`, app API with the Jellyfin token;
@@ -755,9 +786,9 @@ always scrolls the page). Space never presses a focused button
   into videos (the Files extensions, `kindOf`), a folder, an http(s) link,
   an image or nothing; videos win over folders, folders over images.
   `HandoffCard` opens as a popover at the pointer: a video goes up through
-  the shell's put-up (offline: into Files → Recent) or adds its folder to
-  Files; a folder is added to Files and opened; a link fills Library →
-  Link (online the relay mode is picked there). Images are ignored.
+  the shell's put-up (Play when alone; offline that starts solo) or adds
+  its folder to Files; a folder is added to Files and opened; a link fills
+  Library → Link (with others the relay mode is picked there). Images are ignored.
   Nothing happens while a dialog or popover is over the shell.
 - **Sounds** (`sfx/`): the coordinator plays an `SfxCue` for ready,
   unready, force-ready, join, leave, swap and others' chat (feed

docs/HOW-IT-WORKS.md

@@ -44,7 +44,13 @@ A five-minute tour. Details: [ARCHITECTURE.md](ARCHITECTURE.md), wire format:
 - **Dedicated server**: `watch-together-server`, a separate program in the
   release tarball, for an always-on box. See the README.
 
-Friends join either way with Join in the strip at the top of the window.
+Friends join either way with Join a friend in the strip at the top of the
+window; guests need no Jellyfin or account.
+
+- **Watch solo**: put something up without joining or hosting and the
+  app hosts a private server reachable only from this computer, so
+  watching alone works like a session (progress, next episode). Invite
+  friends turns it into a normal hosted server, video and position kept.
 
 ## One session, start to finish
 

packages/server/lib/src/serve.dart

@@ -18,7 +18,8 @@ import 'sync_server.dart';
 /// a file on this machine the hosted file (the hosting app's in-session file
 /// swap; a following `swap` with its name and size puts it up) and answers
 /// `{'ok':true,'name':n,'size':s}` or `{'ok':false}`. Without [events] a
-/// start failure throws.
+/// start failure throws. `'loopbackOnly': true` in [config] (next to the
+/// [AppConfig] keys) binds 127.0.0.1 only: the app's solo session.
 Future<void> serve(Map<String, Object?> config, {SendPort? events}) async {
   StreamSubscription<pkg_logging.LogRecord>? logs;
   if (events != null) {
@@ -32,7 +33,7 @@ Future<void> serve(Map<String, Object?> config, {SendPort? events}) async {
   }
   final SyncServer server;
   try {
-    server = SyncServer(AppConfig.fromMap(config));
+    server = SyncServer(AppConfig.fromMap(config), loopbackOnly: config['loopbackOnly'] == true);
     await server.start();
   } catch (e) {
     await logs?.cancel();

packages/server/lib/src/sync_server.dart

@@ -48,8 +48,12 @@ class SyncServer {
   /// Upstream connections of the Jellyfin relay; created on first use.
   HttpClient? _relayClient;
 
+  /// Listen on 127.0.0.1 only (the app's solo session), not on every
+  /// IPv4 interface.
+  final bool loopbackOnly;
+
   /// [ytDlp] replaces the server's own (tests).
-  SyncServer(this.config, {YtDlp? ytDlp}) {
+  SyncServer(this.config, {YtDlp? ytDlp, this.loopbackOnly = false}) {
     hub = ServerHub(sessions, config.secret,
         hostKey: config.hostKey,
         jellyfin: config.jellyfin,
@@ -131,7 +135,7 @@ class SyncServer {
     await _resolveJellyfinServerId();
     _mountRoutes();
     _server = await _app.serve(
-      address: InternetAddress.anyIPv4,
+      address: loopbackOnly ? InternetAddress.loopbackIPv4 : InternetAddress.anyIPv4,
       port: config.port,
       // A killed isolate never closes its listening socket, so the port stays
       // bound in this process. Shared lets the next server in the same