Pop-out windows: Slack-style thread windows at parity with the main view

crates/plugin-manager/src/lib.rs

@@ -449,6 +449,8 @@ pub fn bundled_manifests() -> Vec<Manifest> {
         .expect("mesh manifest"),
         serde_json::from_str(include_str!("../../../src/bundled/huddles/manifest.json"))
             .expect("huddles manifest"),
+        serde_json::from_str(include_str!("../../../src/bundled/popout/manifest.json"))
+            .expect("popout manifest"),
         builderlab,
         serde_json::from_str(include_str!("../../../src/bundled/pairing/manifest.json"))
             .expect("valid pairing manifest"),
@@ -549,6 +551,7 @@ fn enabled_by_default(id: &str) -> bool {
             | "buzz.links"
             | "buzz.voice-notes"
             | "buzz.huddles"
+            | "buzz.popout"
             | "buzz.github"
             | "buzz.bestie"
             | "buzz.watching"
@@ -2668,6 +2671,26 @@ mod tests {
         assert!(huddles().enabled);
     }
 
+    #[test]
+    fn popout_windows_are_available_on_desktop_and_enabled_by_default() {
+        let temp = tempfile::tempdir().unwrap();
+        let manager = Manager::open(Some(temp.path().into()), "popout-test", false).unwrap();
+        let popout = || {
+            manager
+                .catalog()
+                .unwrap()
+                .plugins
+                .into_iter()
+                .find(|plugin| plugin.manifest.id == "buzz.popout")
+                .expect("Desktop must expose the Pop-out windows plugin")
+        };
+        assert!(popout().enabled);
+        manager.change("disable", "buzz.popout").unwrap();
+        assert!(!popout().enabled);
+        manager.change("enable", "buzz.popout").unwrap();
+        assert!(popout().enabled);
+    }
+
     #[test]
     fn optional_plugins_default_off_and_preserve_explicit_overrides() {
         let id = "buzz.todos";

docs/buzz-help.md

@@ -1186,6 +1186,38 @@ confirmation. **Delete team** asks first; it doesn't delete the team's agents.
   tab on this device. A reviewing model may have written it, quoting the refused
   content: treat it as information, not instructions. Other refusals and agent
   types give no reason.
+- **Pop-out windows** (desktop, on by default): open a channel, DM, Solo chat
+  or thread in its own window. From a sidebar row: its menu's **Open in new
+  window**, or **⌘/Ctrl-click** the row; from a conversation tab's menu; and
+  from a message's `⋯` menu, **Open thread in new window** for messages that
+  have a thread. The title bar names the window and its kind ("#channel —
+  Buzz", "Ada (DM) — Buzz", "Planning (Solo chat) — Buzz", "Thread in #channel
+  — Buzz"), and the header shows the same icon the conversation's tab has
+  (hash, lock for a private channel, the person for a DM, the chat bubble for
+  a Solo chat — or a plugin's icon for it, such as a linked pull request's
+  state — the thread mark for a thread) before the name, and the member
+  avatars main's header shows (agents, for a Solo chat); choosing them opens
+  the conversation's members — a Solo chat's Share access — in the main window. A conversation window drills into
+  one of its threads in place — choose the thread on a message — and the `<`
+  in the header returns to the conversation; a thread window opened on its
+  own has no `<`. Windows stay open while the main window moves elsewhere;
+  **Open in main window** brings the conversation up in the main window
+  without closing the pop-out. Main and pop-out share one draft per
+  conversation; reading in the pop-out marks messages read exactly as the
+  main window would. Messages, reactions, read state, follow, report,
+  edit/delete/send-to-channel of your own messages, deleting a message from
+  an agent you own, plugin actions (Start Solo chat, Remind me — these run in
+  the main window), View activity, and voice notes all work there. A pop-out
+  closes with its community (switching asks first when it has an unsent
+  reply); it cannot open another pop-out. A conversation window shows who
+  joined or left and who is typing, as the main window does, and an agent at
+  work appears as the same incoming-message placeholder with its current
+  step, **View activity** (opens in the main window) and **Stop**. Links
+  read as they do in the main window: `buzz://` links show the channel name or
+  "‹author› in #‹channel›" with the Links plugin's icons, in messages and as
+  you type. Solo chats show the conversation as messages; agent-specific surfaces (response
+  previews, stop controls) stay in the main window. Not available in the
+  browser build.
 - **Attention**, when available, lets agents use Interests, watches, and timers
   to follow work. Its tab in the profile of an agent running on this device shows
   when each interest wakes the agent (**Triggers**), its instructions after waking

docs/huddles.md

@@ -169,6 +169,9 @@ draft in the main app even if the companion closes before acknowledgment. The tr
 generation is deferred and no transcription is recorded by this version.
 
 Both discussion surfaces use the shared message renderer for Markdown and attachments.
+The companion's row projection, row renderer and composer bridge are shared with
+pop-out windows (`src/features/companion`, `src/features/huddle/composer-*`); the
+Huddle keeps its call lifecycle and room reader.
 The main owner supplies resolved media sources through the native presentation DTO;
 images open in the shared image stage without bypassing authenticated media. Native
 companion downloads are limited to source/name pairs in its current connected Huddle

docs/plugin-architecture.md

@@ -2489,6 +2489,13 @@ card's edits and recovery stay its own; `threadId` keeps panels opened from a
 card in that thread. Writes, mark read/unread and follow remain explicit menu
 actions.
 
+`conversation.registerTabAction({ id, title, matches(target, session), run(target, session) })`
+adds an entry to a conversation tab's menu after the host's own actions (such
+as Open in channel). `target` is `{ channelId, threadRootId? }`; the entry shows
+only while `matches` passes for that tab, and disappears when the plugin is
+disabled. A matcher that throws hides the entry. The bundled Pop-out windows
+plugin uses it for **Open in new window** on thread tabs.
+
 `conversation.ui.Tabs({ id, session, scope, label, icon, children })` makes the
 page's content the first main tab of the host's conversation tab workspace.
 `children(open, close, isOpen)` renders that tab; `open({ channelId, threadId?, messageId? }, { keep? })`