sidebar: Switch with `ctrl-tab` (#52423)

Cameron Mcloughlin created

Overrides `ctrl-tab` when the sidebar/agent panel is focused to switch
between recently viewed threads

Release Notes:

- N/A or Added/Fixed/Improved ...

Change summary

assets/keymaps/default-linux.json                    |  11 
assets/keymaps/default-macos.json                    |  11 
assets/keymaps/default-windows.json                  |  11 
crates/agent_ui/src/agent_panel.rs                   |   5 
crates/agent_ui/src/conversation_view/thread_view.rs |   5 
crates/sidebar/src/sidebar.rs                        | 385 +++++++++++++
crates/sidebar/src/sidebar_tests.rs                  | 312 +++++++++++
crates/sidebar/src/thread_switcher.rs                | 378 +++++++++++++
crates/title_bar/src/title_bar.rs                    |   1 
crates/workspace/src/multi_workspace.rs              |  51 +
crates/zed_actions/src/lib.rs                        |  13 
11 files changed, 1,161 insertions(+), 22 deletions(-)

Detailed changes

assets/keymaps/default-linux.json 🔗

@@ -265,6 +265,8 @@
       "ctrl-y": "agent::AllowOnce",
       "ctrl-alt-a": "agent::OpenPermissionDropdown",
       "ctrl-alt-z": "agent::RejectOnce",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -701,6 +703,8 @@
       "ctrl-f": "agents_sidebar::FocusSidebarFilter",
       "ctrl-g": "agents_sidebar::ToggleArchive",
       "shift-backspace": "agent::RemoveSelectedThread",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -710,6 +714,13 @@
       "space": "menu::Confirm",
     },
   },
+  {
+    "context": "ThreadSwitcher",
+    "bindings": {
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }]
+    }
+  },
   {
     "context": "Workspace && debugger_running",
     "bindings": {

assets/keymaps/default-macos.json 🔗

@@ -304,6 +304,8 @@
       "cmd-y": "agent::AllowOnce",
       "cmd-alt-a": "agent::OpenPermissionDropdown",
       "cmd-alt-z": "agent::RejectOnce",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -767,6 +769,8 @@
       "cmd-f": "agents_sidebar::FocusSidebarFilter",
       "cmd-g": "agents_sidebar::ToggleArchive",
       "shift-backspace": "agent::RemoveSelectedThread",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -776,6 +780,13 @@
       "space": "menu::Confirm",
     },
   },
+  {
+    "context": "ThreadSwitcher",
+    "bindings": {
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }]
+    }
+  },
   {
     "context": "Workspace && debugger_running",
     "use_key_equivalents": true,

assets/keymaps/default-windows.json 🔗

@@ -266,6 +266,8 @@
       "shift-alt-a": "agent::AllowOnce",
       "ctrl-alt-a": "agent::OpenPermissionDropdown",
       "shift-alt-z": "agent::RejectOnce",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -703,6 +705,8 @@
       "ctrl-f": "agents_sidebar::FocusSidebarFilter",
       "ctrl-g": "agents_sidebar::ToggleArchive",
       "shift-backspace": "agent::RemoveSelectedThread",
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }],
     },
   },
   {
@@ -712,6 +716,13 @@
       "space": "menu::Confirm",
     },
   },
+  {
+    "context": "ThreadSwitcher",
+    "bindings": {
+      "ctrl-tab": "agents_sidebar::ToggleThreadSwitcher",
+      "ctrl-shift-tab": ["agents_sidebar::ToggleThreadSwitcher", { "select_last": true }]
+    }
+  },
   {
     "context": "ApplicationMenu",
     "use_key_equivalents": true,

crates/agent_ui/src/agent_panel.rs 🔗

@@ -2234,6 +2234,10 @@ impl AgentPanel {
                     AcpThreadViewEvent::FirstSendRequested { content } => {
                         this.handle_first_send_requested(view.clone(), content.clone(), window, cx);
                     }
+                    AcpThreadViewEvent::MessageSentOrQueued => {
+                        let session_id = view.read(cx).thread.read(cx).session_id().clone();
+                        cx.emit(AgentPanelEvent::MessageSentOrQueued { session_id });
+                    }
                 },
             )
         })
@@ -3113,6 +3117,7 @@ pub enum AgentPanelEvent {
     ActiveViewChanged,
     ThreadFocused,
     BackgroundThreadChanged,
+    MessageSentOrQueued { session_id: acp::SessionId },
 }
 
 impl EventEmitter<PanelEvent> for AgentPanel {}

crates/agent_ui/src/conversation_view/thread_view.rs 🔗

@@ -166,6 +166,7 @@ impl ThreadFeedbackState {
 
 pub enum AcpThreadViewEvent {
     FirstSendRequested { content: Vec<acp::ContentBlock> },
+    MessageSentOrQueued,
 }
 
 impl EventEmitter<AcpThreadViewEvent> for ThreadView {}
@@ -907,6 +908,7 @@ impl ThreadView {
                 });
 
         if intercept_first_send {
+            cx.emit(AcpThreadViewEvent::MessageSentOrQueued);
             let content_task = self.resolve_message_contents(&message_editor, cx);
 
             cx.spawn(async move |this, cx| match content_task.await {
@@ -938,6 +940,7 @@ impl ThreadView {
         let has_queued = self.has_queued_messages();
         if is_editor_empty && self.can_fast_track_queue && has_queued {
             self.can_fast_track_queue = false;
+            cx.emit(AcpThreadViewEvent::MessageSentOrQueued);
             self.send_queued_message_at_index(0, true, window, cx);
             return;
         }
@@ -947,6 +950,7 @@ impl ThreadView {
         }
 
         if is_generating {
+            cx.emit(AcpThreadViewEvent::MessageSentOrQueued);
             self.queue_message(message_editor, window, cx);
             return;
         }
@@ -988,6 +992,7 @@ impl ThreadView {
             }
         }
 
+        cx.emit(AcpThreadViewEvent::MessageSentOrQueued);
         self.send_impl(message_editor, window, cx)
     }
 

crates/sidebar/src/sidebar.rs 🔗

@@ -1,3 +1,5 @@
+mod thread_switcher;
+
 use acp_thread::ThreadStatus;
 use action_log::DiffStats;
 use agent_client_protocol::{self as acp};
@@ -9,7 +11,7 @@ use agent_ui::threads_archive_view::{
 use agent_ui::{
     Agent, AgentPanel, AgentPanelEvent, DEFAULT_THREAD_TITLE, NewThread, RemoveSelectedThread,
 };
-use chrono::Utc;
+use chrono::{DateTime, Utc};
 use editor::Editor;
 use feature_flags::{AgentV2FeatureFlag, FeatureFlagViewExt as _};
 use gpui::{
@@ -44,7 +46,9 @@ use workspace::{
 use zed_actions::OpenRecent;
 use zed_actions::editor::{MoveDown, MoveUp};
 
-use zed_actions::agents_sidebar::FocusSidebarFilter;
+use zed_actions::agents_sidebar::{FocusSidebarFilter, ToggleThreadSwitcher};
+
+use crate::thread_switcher::{ThreadSwitcher, ThreadSwitcherEntry, ThreadSwitcherEvent};
 
 use crate::project_group_builder::ProjectGroupBuilder;
 
@@ -312,6 +316,16 @@ pub struct Sidebar {
     hovered_thread_index: Option<usize>,
     collapsed_groups: HashSet<PathList>,
     expanded_groups: HashMap<PathList, usize>,
+    /// Updated only in response to explicit user actions (clicking a
+    /// thread, confirming in the thread switcher, etc.) — never from
+    /// background data changes. Used to sort the thread switcher popup.
+    thread_last_accessed: HashMap<acp::SessionId, DateTime<Utc>>,
+    /// Updated when the user presses a key to send or queue a message.
+    /// Used for sorting threads in the sidebar and as a secondary sort
+    /// key in the thread switcher.
+    thread_last_message_sent_or_queued: HashMap<acp::SessionId, DateTime<Utc>>,
+    thread_switcher: Option<Entity<ThreadSwitcher>>,
+    _thread_switcher_subscriptions: Vec<gpui::Subscription>,
     view: SidebarView,
     recent_projects_popover_handle: PopoverMenuHandle<SidebarRecentProjects>,
     project_header_menu_ix: Option<usize>,
@@ -404,6 +418,10 @@ impl Sidebar {
             hovered_thread_index: None,
             collapsed_groups: HashSet::new(),
             expanded_groups: HashMap::new(),
+            thread_last_accessed: HashMap::new(),
+            thread_last_message_sent_or_queued: HashMap::new(),
+            thread_switcher: None,
+            _thread_switcher_subscriptions: Vec::new(),
             view: SidebarView::default(),
             recent_projects_popover_handle: PopoverMenuHandle::default(),
             project_header_menu_ix: None,
@@ -506,6 +524,10 @@ impl Sidebar {
                 AgentPanelEvent::ThreadFocused | AgentPanelEvent::BackgroundThreadChanged => {
                     this.update_entries(cx);
                 }
+                AgentPanelEvent::MessageSentOrQueued { session_id } => {
+                    this.record_thread_message_sent(session_id);
+                    this.update_entries(cx);
+                }
             },
         )
         .detach();
@@ -779,7 +801,7 @@ impl Sidebar {
                     }
                 }
 
-                // Load threads from linked git worktrees whose
+                // Load threads from linked git worktrees
                 // canonical paths belong to this group.
                 let linked_worktree_queries = group
                     .workspaces
@@ -872,8 +894,18 @@ impl Sidebar {
                 }
 
                 threads.sort_by(|a, b| {
-                    let a_time = a.session_info.created_at.or(a.session_info.updated_at);
-                    let b_time = b.session_info.created_at.or(b.session_info.updated_at);
+                    let a_time = self
+                        .thread_last_message_sent_or_queued
+                        .get(&a.session_info.session_id)
+                        .copied()
+                        .or(a.session_info.created_at)
+                        .or(a.session_info.updated_at);
+                    let b_time = self
+                        .thread_last_message_sent_or_queued
+                        .get(&b.session_info.session_id)
+                        .copied()
+                        .or(b.session_info.created_at)
+                        .or(b.session_info.updated_at);
                     b_time.cmp(&a_time)
                 });
             } else {
@@ -1022,6 +1054,11 @@ impl Sidebar {
         // the build pass (no extra scan needed).
         notified_threads.retain(|id| current_session_ids.contains(id));
 
+        self.thread_last_accessed
+            .retain(|id, _| current_session_ids.contains(id));
+        self.thread_last_message_sent_or_queued
+            .retain(|id, _| current_session_ids.contains(id));
+
         self.contents = SidebarContents {
             entries,
             notified_threads,
@@ -1881,6 +1918,7 @@ impl Sidebar {
         workspace: &Entity<Workspace>,
         agent: Agent,
         session_info: acp_thread::AgentSessionInfo,
+        focus: bool,
         window: &mut Window,
         cx: &mut App,
     ) {
@@ -1895,7 +1933,7 @@ impl Sidebar {
                     session_info.session_id,
                     session_info.work_dirs,
                     session_info.title,
-                    true,
+                    focus,
                     window,
                     cx,
                 );
@@ -1919,12 +1957,13 @@ impl Sidebar {
         // immediately, rather than waiting for a deferred AgentPanel
         // event which can race with ActiveWorkspaceChanged clearing it.
         self.focused_thread = Some(session_info.session_id.clone());
+        self.record_thread_access(&session_info.session_id);
 
         multi_workspace.update(cx, |multi_workspace, cx| {
             multi_workspace.activate(workspace.clone(), cx);
         });
 
-        Self::load_agent_thread_in_workspace(workspace, agent, session_info, window, cx);
+        Self::load_agent_thread_in_workspace(workspace, agent, session_info, true, window, cx);
 
         self.update_entries(cx);
     }
@@ -1943,7 +1982,14 @@ impl Sidebar {
             .update(cx, |multi_workspace, window, cx| {
                 window.activate_window();
                 multi_workspace.activate(workspace.clone(), cx);
-                Self::load_agent_thread_in_workspace(&workspace, agent, session_info, window, cx);
+                Self::load_agent_thread_in_workspace(
+                    &workspace,
+                    agent,
+                    session_info,
+                    true,
+                    window,
+                    cx,
+                );
             })
             .log_err()
             .is_some();
@@ -1958,7 +2004,8 @@ impl Sidebar {
                 .and_then(|sidebar| sidebar.downcast::<Self>().ok())
             {
                 target_sidebar.update(cx, |sidebar, cx| {
-                    sidebar.focused_thread = Some(target_session_id);
+                    sidebar.focused_thread = Some(target_session_id.clone());
+                    sidebar.record_thread_access(&target_session_id);
                     sidebar.update_entries(cx);
                 });
             }
@@ -2287,8 +2334,10 @@ impl Sidebar {
             });
 
             if let Some(next) = next_thread {
-                self.focused_thread = Some(next.session_info.session_id.clone());
-
+                let next_session_id = next.session_info.session_id.clone();
+                let next_agent = next.agent.clone();
+                let next_work_dirs = next.session_info.work_dirs.clone();
+                let next_title = next.session_info.title.clone();
                 // Use the thread's own workspace when it has one open (e.g. an absorbed
                 // linked worktree thread that appears under the main workspace's header
                 // but belongs to its own workspace). Loading into the wrong panel binds
@@ -2298,15 +2347,17 @@ impl Sidebar {
                     ThreadEntryWorkspace::Open(ws) => Some(ws.clone()),
                     ThreadEntryWorkspace::Closed(_) => group_workspace,
                 };
+                self.focused_thread = Some(next_session_id.clone());
+                self.record_thread_access(&next_session_id);
 
                 if let Some(workspace) = target_workspace {
                     if let Some(agent_panel) = workspace.read(cx).panel::<AgentPanel>(cx) {
                         agent_panel.update(cx, |panel, cx| {
                             panel.load_agent_thread(
-                                next.agent.clone(),
-                                next.session_info.session_id.clone(),
-                                next.session_info.work_dirs.clone(),
-                                next.session_info.title.clone(),
+                                next_agent,
+                                next_session_id,
+                                next_work_dirs,
+                                next_title,
                                 true,
                                 window,
                                 cx,
@@ -2349,6 +2400,292 @@ impl Sidebar {
         self.archive_thread(&session_id, window, cx);
     }
 
+    fn record_thread_access(&mut self, session_id: &acp::SessionId) {
+        self.thread_last_accessed
+            .insert(session_id.clone(), Utc::now());
+    }
+
+    fn record_thread_message_sent(&mut self, session_id: &acp::SessionId) {
+        self.thread_last_message_sent_or_queued
+            .insert(session_id.clone(), Utc::now());
+    }
+
+    fn mru_threads_for_switcher(&self, _cx: &App) -> Vec<ThreadSwitcherEntry> {
+        let mut current_header_workspace: Option<Entity<Workspace>> = None;
+        let mut entries: Vec<ThreadSwitcherEntry> = self
+            .contents
+            .entries
+            .iter()
+            .filter_map(|entry| match entry {
+                ListEntry::ProjectHeader { workspace, .. } => {
+                    current_header_workspace = Some(workspace.clone());
+                    None
+                }
+                ListEntry::Thread(thread) => {
+                    let workspace = match &thread.workspace {
+                        ThreadEntryWorkspace::Open(workspace) => workspace.clone(),
+                        ThreadEntryWorkspace::Closed(_) => {
+                            current_header_workspace.as_ref()?.clone()
+                        }
+                    };
+                    let notified = self
+                        .contents
+                        .is_thread_notified(&thread.session_info.session_id);
+                    let timestamp: SharedString = self
+                        .thread_last_message_sent_or_queued
+                        .get(&thread.session_info.session_id)
+                        .copied()
+                        .or(thread.session_info.created_at)
+                        .or(thread.session_info.updated_at)
+                        .map(format_history_entry_timestamp)
+                        .unwrap_or_default()
+                        .into();
+                    Some(ThreadSwitcherEntry {
+                        session_id: thread.session_info.session_id.clone(),
+                        title: thread
+                            .session_info
+                            .title
+                            .clone()
+                            .unwrap_or_else(|| "Untitled".into()),
+                        icon: thread.icon,
+                        icon_from_external_svg: thread.icon_from_external_svg.clone(),
+                        status: thread.status,
+                        agent: thread.agent.clone(),
+                        session_info: thread.session_info.clone(),
+                        workspace,
+                        worktree_name: thread.worktrees.first().map(|wt| wt.name.clone()),
+
+                        diff_stats: thread.diff_stats,
+                        is_title_generating: thread.is_title_generating,
+                        notified,
+                        timestamp,
+                    })
+                }
+                _ => None,
+            })
+            .collect();
+
+        entries.sort_by(|a, b| {
+            let a_accessed = self.thread_last_accessed.get(&a.session_id);
+            let b_accessed = self.thread_last_accessed.get(&b.session_id);
+
+            match (a_accessed, b_accessed) {
+                (Some(a_time), Some(b_time)) => b_time.cmp(a_time),
+                (Some(_), None) => std::cmp::Ordering::Less,
+                (None, Some(_)) => std::cmp::Ordering::Greater,
+                (None, None) => {
+                    let a_sent = self.thread_last_message_sent_or_queued.get(&a.session_id);
+                    let b_sent = self.thread_last_message_sent_or_queued.get(&b.session_id);
+
+                    match (a_sent, b_sent) {
+                        (Some(a_time), Some(b_time)) => b_time.cmp(a_time),
+                        (Some(_), None) => std::cmp::Ordering::Less,
+                        (None, Some(_)) => std::cmp::Ordering::Greater,
+                        (None, None) => {
+                            let a_time = a.session_info.created_at.or(a.session_info.updated_at);
+                            let b_time = b.session_info.created_at.or(b.session_info.updated_at);
+                            b_time.cmp(&a_time)
+                        }
+                    }
+                }
+            }
+        });
+
+        entries
+    }
+
+    fn dismiss_thread_switcher(&mut self, cx: &mut Context<Self>) {
+        self.thread_switcher = None;
+        self._thread_switcher_subscriptions.clear();
+        if let Some(mw) = self.multi_workspace.upgrade() {
+            mw.update(cx, |mw, cx| {
+                mw.set_sidebar_overlay(None, cx);
+            });
+        }
+    }
+
+    fn on_toggle_thread_switcher(
+        &mut self,
+        action: &ToggleThreadSwitcher,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.toggle_thread_switcher_impl(action.select_last, window, cx);
+    }
+
+    fn toggle_thread_switcher_impl(
+        &mut self,
+        select_last: bool,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        if let Some(thread_switcher) = &self.thread_switcher {
+            thread_switcher.update(cx, |switcher, cx| {
+                if select_last {
+                    switcher.select_last(cx);
+                } else {
+                    switcher.cycle_selection(cx);
+                }
+            });
+            return;
+        }
+
+        let entries = self.mru_threads_for_switcher(cx);
+        if entries.len() < 2 {
+            return;
+        }
+
+        let weak_multi_workspace = self.multi_workspace.clone();
+
+        let original_agent = self
+            .focused_thread
+            .as_ref()
+            .and_then(|focused_id| entries.iter().find(|e| &e.session_id == focused_id))
+            .map(|e| e.agent.clone());
+        let original_session_info = self
+            .focused_thread
+            .as_ref()
+            .and_then(|focused_id| entries.iter().find(|e| &e.session_id == focused_id))
+            .map(|e| e.session_info.clone());
+        let original_workspace = self
+            .multi_workspace
+            .upgrade()
+            .map(|mw| mw.read(cx).workspace().clone());
+
+        let thread_switcher = cx.new(|cx| ThreadSwitcher::new(entries, select_last, window, cx));
+
+        let mut subscriptions = Vec::new();
+
+        subscriptions.push(cx.subscribe_in(&thread_switcher, window, {
+            let thread_switcher = thread_switcher.clone();
+            move |this, _emitter, event: &ThreadSwitcherEvent, window, cx| match event {
+                ThreadSwitcherEvent::Preview {
+                    agent,
+                    session_info,
+                    workspace,
+                } => {
+                    if let Some(mw) = weak_multi_workspace.upgrade() {
+                        mw.update(cx, |mw, cx| {
+                            mw.activate(workspace.clone(), cx);
+                        });
+                    }
+                    this.focused_thread = Some(session_info.session_id.clone());
+                    this.update_entries(cx);
+                    Self::load_agent_thread_in_workspace(
+                        workspace,
+                        agent.clone(),
+                        session_info.clone(),
+                        false,
+                        window,
+                        cx,
+                    );
+                    let focus = thread_switcher.focus_handle(cx);
+                    window.focus(&focus, cx);
+                }
+                ThreadSwitcherEvent::Confirmed {
+                    agent,
+                    session_info,
+                    workspace,
+                } => {
+                    if let Some(mw) = weak_multi_workspace.upgrade() {
+                        mw.update(cx, |mw, cx| {
+                            mw.activate(workspace.clone(), cx);
+                        });
+                    }
+                    this.record_thread_access(&session_info.session_id);
+                    this.focused_thread = Some(session_info.session_id.clone());
+                    this.update_entries(cx);
+                    Self::load_agent_thread_in_workspace(
+                        workspace,
+                        agent.clone(),
+                        session_info.clone(),
+                        false,
+                        window,
+                        cx,
+                    );
+                    this.dismiss_thread_switcher(cx);
+                    workspace.update(cx, |workspace, cx| {
+                        workspace.focus_panel::<AgentPanel>(window, cx);
+                    });
+                }
+                ThreadSwitcherEvent::Dismissed => {
+                    if let Some(mw) = weak_multi_workspace.upgrade() {
+                        if let Some(original_ws) = &original_workspace {
+                            mw.update(cx, |mw, cx| {
+                                mw.activate(original_ws.clone(), cx);
+                            });
+                        }
+                    }
+                    if let Some(session_info) = &original_session_info {
+                        this.focused_thread = Some(session_info.session_id.clone());
+                        this.update_entries(cx);
+                        let agent = original_agent.clone().unwrap_or(Agent::NativeAgent);
+                        if let Some(original_ws) = &original_workspace {
+                            Self::load_agent_thread_in_workspace(
+                                original_ws,
+                                agent,
+                                session_info.clone(),
+                                false,
+                                window,
+                                cx,
+                            );
+                        }
+                    }
+                    this.dismiss_thread_switcher(cx);
+                }
+            }
+        }));
+
+        subscriptions.push(cx.subscribe_in(
+            &thread_switcher,
+            window,
+            |this, _emitter, _event: &gpui::DismissEvent, _window, cx| {
+                this.dismiss_thread_switcher(cx);
+            },
+        ));
+
+        let focus = thread_switcher.focus_handle(cx);
+        let overlay_view = gpui::AnyView::from(thread_switcher.clone());
+
+        // Replay the initial preview that was emitted during construction
+        // before subscriptions were wired up.
+        let initial_preview = thread_switcher.read(cx).selected_entry().map(|entry| {
+            (
+                entry.agent.clone(),
+                entry.session_info.clone(),
+                entry.workspace.clone(),
+            )
+        });
+
+        self.thread_switcher = Some(thread_switcher);
+        self._thread_switcher_subscriptions = subscriptions;
+        if let Some(mw) = self.multi_workspace.upgrade() {
+            mw.update(cx, |mw, cx| {
+                mw.set_sidebar_overlay(Some(overlay_view), cx);
+            });
+        }
+
+        if let Some((agent, session_info, workspace)) = initial_preview {
+            if let Some(mw) = self.multi_workspace.upgrade() {
+                mw.update(cx, |mw, cx| {
+                    mw.activate(workspace.clone(), cx);
+                });
+            }
+            self.focused_thread = Some(session_info.session_id.clone());
+            self.update_entries(cx);
+            Self::load_agent_thread_in_workspace(
+                &workspace,
+                agent,
+                session_info,
+                false,
+                window,
+                cx,
+            );
+        }
+
+        window.focus(&focus, cx);
+    }
+
     fn render_thread(
         &self,
         ix: usize,
@@ -2381,9 +2718,11 @@ impl Sidebar {
 
         let id = SharedString::from(format!("thread-entry-{}", ix));
 
-        let timestamp = thread
-            .session_info
-            .created_at
+        let timestamp = self
+            .thread_last_message_sent_or_queued
+            .get(&thread.session_info.session_id)
+            .copied()
+            .or(thread.session_info.created_at)
             .or(thread.session_info.updated_at)
             .map(format_history_entry_timestamp);
 
@@ -3017,6 +3356,15 @@ impl WorkspaceSidebar for Sidebar {
         self.selection = None;
         cx.notify();
     }
+
+    fn toggle_thread_switcher(
+        &mut self,
+        select_last: bool,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.toggle_thread_switcher_impl(select_last, window, cx);
+    }
 }
 
 impl Focusable for Sidebar {
@@ -3060,6 +3408,7 @@ impl Render for Sidebar {
             .on_action(cx.listener(Self::new_thread_in_group))
             .on_action(cx.listener(Self::toggle_archive))
             .on_action(cx.listener(Self::focus_sidebar_filter))
+            .on_action(cx.listener(Self::on_toggle_thread_switcher))
             .on_action(cx.listener(|this, _: &OpenRecent, window, cx| {
                 this.recent_projects_popover_handle.toggle(window, cx);
             }))

crates/sidebar/src/sidebar_tests.rs 🔗

@@ -4127,6 +4127,318 @@ async fn test_linked_worktree_threads_not_duplicated_across_groups(cx: &mut Test
     );
 }
 
+#[gpui::test]
+async fn test_thread_switcher_ordering(cx: &mut TestAppContext) {
+    let project = init_test_project_with_agent_panel("/my-project", cx).await;
+    let (multi_workspace, cx) =
+        cx.add_window_view(|window, cx| MultiWorkspace::test_new(project.clone(), window, cx));
+    let (sidebar, panel) = setup_sidebar_with_agent_panel(&multi_workspace, &project, cx);
+
+    let path_list = PathList::new(&[std::path::PathBuf::from("/my-project")]);
+
+    let switcher_ids =
+        |sidebar: &Entity<Sidebar>, cx: &mut gpui::VisualTestContext| -> Vec<acp::SessionId> {
+            sidebar.read_with(cx, |sidebar, cx| {
+                let switcher = sidebar
+                    .thread_switcher
+                    .as_ref()
+                    .expect("switcher should be open");
+                switcher
+                    .read(cx)
+                    .entries()
+                    .iter()
+                    .map(|e| e.session_id.clone())
+                    .collect()
+            })
+        };
+
+    let switcher_selected_id =
+        |sidebar: &Entity<Sidebar>, cx: &mut gpui::VisualTestContext| -> acp::SessionId {
+            sidebar.read_with(cx, |sidebar, cx| {
+                let switcher = sidebar
+                    .thread_switcher
+                    .as_ref()
+                    .expect("switcher should be open");
+                let s = switcher.read(cx);
+                s.selected_entry()
+                    .expect("should have selection")
+                    .session_id
+                    .clone()
+            })
+        };
+
+    // ── Setup: create three threads with distinct created_at times ──────
+    // Thread C (oldest), Thread B, Thread A (newest) — by created_at.
+    // We send messages in each so they also get last_message_sent_or_queued timestamps.
+    let connection_c = StubAgentConnection::new();
+    connection_c.set_next_prompt_updates(vec![acp::SessionUpdate::AgentMessageChunk(
+        acp::ContentChunk::new("Done C".into()),
+    )]);
+    open_thread_with_connection(&panel, connection_c, cx);
+    send_message(&panel, cx);
+    let session_id_c = active_session_id(&panel, cx);
+    cx.update(|_, cx| {
+        SidebarThreadMetadataStore::global(cx).update(cx, |store, cx| {
+            store.save(
+                ThreadMetadata {
+                    session_id: session_id_c.clone(),
+                    agent_id: None,
+                    title: "Thread C".into(),
+                    updated_at: chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 1, 0, 0, 0)
+                        .unwrap(),
+                    created_at: Some(
+                        chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 1, 0, 0, 0).unwrap(),
+                    ),
+                    folder_paths: path_list.clone(),
+                },
+                cx,
+            )
+        })
+    });
+    cx.run_until_parked();
+
+    let connection_b = StubAgentConnection::new();
+    connection_b.set_next_prompt_updates(vec![acp::SessionUpdate::AgentMessageChunk(
+        acp::ContentChunk::new("Done B".into()),
+    )]);
+    open_thread_with_connection(&panel, connection_b, cx);
+    send_message(&panel, cx);
+    let session_id_b = active_session_id(&panel, cx);
+    cx.update(|_, cx| {
+        SidebarThreadMetadataStore::global(cx).update(cx, |store, cx| {
+            store.save(
+                ThreadMetadata {
+                    session_id: session_id_b.clone(),
+                    agent_id: None,
+                    title: "Thread B".into(),
+                    updated_at: chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 2, 0, 0, 0)
+                        .unwrap(),
+                    created_at: Some(
+                        chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 2, 0, 0, 0).unwrap(),
+                    ),
+                    folder_paths: path_list.clone(),
+                },
+                cx,
+            )
+        })
+    });
+    cx.run_until_parked();
+
+    let connection_a = StubAgentConnection::new();
+    connection_a.set_next_prompt_updates(vec![acp::SessionUpdate::AgentMessageChunk(
+        acp::ContentChunk::new("Done A".into()),
+    )]);
+    open_thread_with_connection(&panel, connection_a, cx);
+    send_message(&panel, cx);
+    let session_id_a = active_session_id(&panel, cx);
+    cx.update(|_, cx| {
+        SidebarThreadMetadataStore::global(cx).update(cx, |store, cx| {
+            store.save(
+                ThreadMetadata {
+                    session_id: session_id_a.clone(),
+                    agent_id: None,
+                    title: "Thread A".into(),
+                    updated_at: chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 3, 0, 0, 0)
+                        .unwrap(),
+                    created_at: Some(
+                        chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 1, 3, 0, 0, 0).unwrap(),
+                    ),
+                    folder_paths: path_list.clone(),
+                },
+                cx,
+            )
+        })
+    });
+    cx.run_until_parked();
+
+    // All three threads are now live. Thread A was opened last, so it's
+    // the one being viewed. Opening each thread called record_thread_access,
+    // so all three have last_accessed_at set.
+    // Access order is: A (most recent), B, C (oldest).
+
+    // ── 1. Open switcher: threads sorted by last_accessed_at ───────────
+    open_and_focus_sidebar(&sidebar, cx);
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        sidebar.on_toggle_thread_switcher(&ToggleThreadSwitcher::default(), window, cx);
+    });
+    cx.run_until_parked();
+
+    // All three have last_accessed_at, so they sort by access time.
+    // A was accessed most recently (it's the currently viewed thread),
+    // then B, then C.
+    assert_eq!(
+        switcher_ids(&sidebar, cx),
+        vec![
+            session_id_a.clone(),
+            session_id_b.clone(),
+            session_id_c.clone()
+        ],
+    );
+    // First ctrl-tab selects the second entry (B).
+    assert_eq!(switcher_selected_id(&sidebar, cx), session_id_b);
+
+    // Dismiss the switcher without confirming.
+    sidebar.update_in(cx, |sidebar, _window, cx| {
+        sidebar.dismiss_thread_switcher(cx);
+    });
+    cx.run_until_parked();
+
+    // ── 2. Confirm on Thread C: it becomes most-recently-accessed ──────
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        sidebar.on_toggle_thread_switcher(&ToggleThreadSwitcher::default(), window, cx);
+    });
+    cx.run_until_parked();
+
+    // Cycle twice to land on Thread C (index 2).
+    sidebar.read_with(cx, |sidebar, cx| {
+        let switcher = sidebar.thread_switcher.as_ref().unwrap();
+        assert_eq!(switcher.read(cx).selected_index(), 1);
+    });
+    sidebar.update_in(cx, |sidebar, _window, cx| {
+        sidebar
+            .thread_switcher
+            .as_ref()
+            .unwrap()
+            .update(cx, |s, cx| s.cycle_selection(cx));
+    });
+    cx.run_until_parked();
+    assert_eq!(switcher_selected_id(&sidebar, cx), session_id_c);
+
+    // Confirm on Thread C.
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        let switcher = sidebar.thread_switcher.as_ref().unwrap();
+        let focus = switcher.focus_handle(cx);
+        focus.dispatch_action(&menu::Confirm, window, cx);
+    });
+    cx.run_until_parked();
+
+    // Switcher should be dismissed after confirm.
+    sidebar.read_with(cx, |sidebar, _cx| {
+        assert!(
+            sidebar.thread_switcher.is_none(),
+            "switcher should be dismissed"
+        );
+    });
+
+    // Re-open switcher: Thread C is now most-recently-accessed.
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        sidebar.on_toggle_thread_switcher(&ToggleThreadSwitcher::default(), window, cx);
+    });
+    cx.run_until_parked();
+
+    assert_eq!(
+        switcher_ids(&sidebar, cx),
+        vec![
+            session_id_c.clone(),
+            session_id_a.clone(),
+            session_id_b.clone()
+        ],
+    );
+
+    sidebar.update_in(cx, |sidebar, _window, cx| {
+        sidebar.dismiss_thread_switcher(cx);
+    });
+    cx.run_until_parked();
+
+    // ── 3. Add a historical thread (no last_accessed_at, no message sent) ──
+    // This thread was never opened in a panel — it only exists in metadata.
+    cx.update(|_, cx| {
+        SidebarThreadMetadataStore::global(cx).update(cx, |store, cx| {
+            store.save(
+                ThreadMetadata {
+                    session_id: acp::SessionId::new(Arc::from("thread-historical")),
+                    agent_id: None,
+                    title: "Historical Thread".into(),
+                    updated_at: chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 6, 1, 0, 0, 0)
+                        .unwrap(),
+                    created_at: Some(
+                        chrono::TimeZone::with_ymd_and_hms(&Utc, 2024, 6, 1, 0, 0, 0).unwrap(),
+                    ),
+                    folder_paths: path_list.clone(),
+                },
+                cx,
+            )
+        })
+    });
+    cx.run_until_parked();
+
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        sidebar.on_toggle_thread_switcher(&ToggleThreadSwitcher::default(), window, cx);
+    });
+    cx.run_until_parked();
+
+    // Historical Thread has no last_accessed_at and no last_message_sent_or_queued,
+    // so it falls to tier 3 (sorted by created_at). It should appear after all
+    // accessed threads, even though its created_at (June 2024) is much later
+    // than the others.
+    //
+    // But the live threads (A, B, C) each had send_message called which sets
+    // last_message_sent_or_queued. So for the accessed threads (tier 1) the
+    // sort key is last_accessed_at; for Historical Thread (tier 3) it's created_at.
+    let session_id_hist = acp::SessionId::new(Arc::from("thread-historical"));
+    let ids = switcher_ids(&sidebar, cx);
+    assert_eq!(
+        ids,
+        vec![
+            session_id_c.clone(),
+            session_id_a.clone(),
+            session_id_b.clone(),
+            session_id_hist.clone()
+        ],
+    );
+
+    sidebar.update_in(cx, |sidebar, _window, cx| {
+        sidebar.dismiss_thread_switcher(cx);
+    });
+    cx.run_until_parked();
+
+    // ── 4. Add another historical thread with older created_at ─────────
+    cx.update(|_, cx| {
+        SidebarThreadMetadataStore::global(cx).update(cx, |store, cx| {
+            store.save(
+                ThreadMetadata {
+                    session_id: acp::SessionId::new(Arc::from("thread-old-historical")),
+                    agent_id: None,
+                    title: "Old Historical Thread".into(),
+                    updated_at: chrono::TimeZone::with_ymd_and_hms(&Utc, 2023, 6, 1, 0, 0, 0)
+                        .unwrap(),
+                    created_at: Some(
+                        chrono::TimeZone::with_ymd_and_hms(&Utc, 2023, 6, 1, 0, 0, 0).unwrap(),
+                    ),
+                    folder_paths: path_list.clone(),
+                },
+                cx,
+            )
+        })
+    });
+    cx.run_until_parked();
+
+    sidebar.update_in(cx, |sidebar, window, cx| {
+        sidebar.on_toggle_thread_switcher(&ToggleThreadSwitcher::default(), window, cx);
+    });
+    cx.run_until_parked();
+
+    // Both historical threads have no access or message times. They should
+    // appear after accessed threads, sorted by created_at (newest first).
+    let session_id_old_hist = acp::SessionId::new(Arc::from("thread-old-historical"));
+    let ids = switcher_ids(&sidebar, cx);
+    assert_eq!(
+        ids,
+        vec![
+            session_id_c.clone(),
+            session_id_a.clone(),
+            session_id_b.clone(),
+            session_id_hist,
+            session_id_old_hist,
+        ],
+    );
+
+    sidebar.update_in(cx, |sidebar, _window, cx| {
+        sidebar.dismiss_thread_switcher(cx);
+    });
+    cx.run_until_parked();
+}
+
 mod property_test {
     use super::*;
     use gpui::EntityId;

crates/sidebar/src/thread_switcher.rs 🔗

@@ -0,0 +1,378 @@
+use acp_thread;
+use action_log::DiffStats;
+use agent_client_protocol as acp;
+use agent_ui::Agent;
+use gpui::{
+    Action as _, Animation, AnimationExt, AnyElement, DismissEvent, Entity, EventEmitter,
+    FocusHandle, Focusable, Hsla, Modifiers, ModifiersChangedEvent, Render, SharedString,
+    prelude::*, pulsating_between,
+};
+use std::time::Duration;
+use ui::{
+    AgentThreadStatus, Color, CommonAnimationExt, DecoratedIcon, DiffStat, Icon, IconDecoration,
+    IconDecorationKind, IconName, IconSize, Label, LabelSize, prelude::*,
+};
+use workspace::{ModalView, Workspace};
+use zed_actions::agents_sidebar::ToggleThreadSwitcher;
+
+const PANEL_WIDTH_REMS: f32 = 28.;
+
+pub(crate) struct ThreadSwitcherEntry {
+    pub session_id: acp::SessionId,
+    pub title: SharedString,
+    pub icon: IconName,
+    pub icon_from_external_svg: Option<SharedString>,
+    pub status: AgentThreadStatus,
+    pub agent: Agent,
+    pub session_info: acp_thread::AgentSessionInfo,
+    pub workspace: Entity<Workspace>,
+    pub worktree_name: Option<SharedString>,
+    pub diff_stats: DiffStats,
+    pub is_title_generating: bool,
+    pub notified: bool,
+    pub timestamp: SharedString,
+}
+
+pub(crate) enum ThreadSwitcherEvent {
+    Preview {
+        agent: Agent,
+        session_info: acp_thread::AgentSessionInfo,
+        workspace: Entity<Workspace>,
+    },
+    Confirmed {
+        agent: Agent,
+        session_info: acp_thread::AgentSessionInfo,
+        workspace: Entity<Workspace>,
+    },
+    Dismissed,
+}
+
+pub(crate) struct ThreadSwitcher {
+    focus_handle: FocusHandle,
+    entries: Vec<ThreadSwitcherEntry>,
+    selected_index: usize,
+    init_modifiers: Option<Modifiers>,
+}
+
+impl ThreadSwitcher {
+    pub fn new(
+        entries: Vec<ThreadSwitcherEntry>,
+        select_last: bool,
+        window: &mut gpui::Window,
+        cx: &mut Context<Self>,
+    ) -> Self {
+        let init_modifiers = window.modifiers().modified().then_some(window.modifiers());
+        let selected_index = if entries.is_empty() {
+            0
+        } else if select_last {
+            entries.len() - 1
+        } else {
+            1.min(entries.len().saturating_sub(1))
+        };
+
+        if let Some(entry) = entries.get(selected_index) {
+            cx.emit(ThreadSwitcherEvent::Preview {
+                agent: entry.agent.clone(),
+                session_info: entry.session_info.clone(),
+                workspace: entry.workspace.clone(),
+            });
+        }
+
+        let focus_handle = cx.focus_handle();
+        cx.on_focus_out(&focus_handle, window, |_this, _event, _window, cx| {
+            cx.emit(ThreadSwitcherEvent::Dismissed);
+            cx.emit(DismissEvent);
+        })
+        .detach();
+
+        Self {
+            focus_handle,
+            entries,
+            selected_index,
+            init_modifiers,
+        }
+    }
+
+    pub fn selected_entry(&self) -> Option<&ThreadSwitcherEntry> {
+        self.entries.get(self.selected_index)
+    }
+
+    #[cfg(test)]
+    pub fn entries(&self) -> &[ThreadSwitcherEntry] {
+        &self.entries
+    }
+
+    #[cfg(test)]
+    pub fn selected_index(&self) -> usize {
+        self.selected_index
+    }
+
+    pub fn cycle_selection(&mut self, cx: &mut Context<Self>) {
+        if self.entries.is_empty() {
+            return;
+        }
+        self.selected_index = (self.selected_index + 1) % self.entries.len();
+        self.emit_preview(cx);
+    }
+
+    pub fn select_last(&mut self, cx: &mut Context<Self>) {
+        if self.entries.is_empty() {
+            return;
+        }
+        if self.selected_index == 0 {
+            self.selected_index = self.entries.len() - 1;
+        } else {
+            self.selected_index -= 1;
+        }
+        self.emit_preview(cx);
+    }
+
+    fn emit_preview(&mut self, cx: &mut Context<Self>) {
+        if let Some(entry) = self.entries.get(self.selected_index) {
+            cx.emit(ThreadSwitcherEvent::Preview {
+                agent: entry.agent.clone(),
+                session_info: entry.session_info.clone(),
+                workspace: entry.workspace.clone(),
+            });
+        }
+    }
+
+    fn confirm(&mut self, _: &menu::Confirm, _window: &mut gpui::Window, cx: &mut Context<Self>) {
+        if let Some(entry) = self.entries.get(self.selected_index) {
+            cx.emit(ThreadSwitcherEvent::Confirmed {
+                agent: entry.agent.clone(),
+                session_info: entry.session_info.clone(),
+                workspace: entry.workspace.clone(),
+            });
+        }
+        cx.emit(DismissEvent);
+    }
+
+    fn cancel(&mut self, _: &menu::Cancel, _window: &mut gpui::Window, cx: &mut Context<Self>) {
+        cx.emit(ThreadSwitcherEvent::Dismissed);
+        cx.emit(DismissEvent);
+    }
+
+    fn toggle(
+        &mut self,
+        action: &ToggleThreadSwitcher,
+        _window: &mut gpui::Window,
+        cx: &mut Context<Self>,
+    ) {
+        if action.select_last {
+            self.select_last(cx);
+        } else {
+            self.cycle_selection(cx);
+        }
+    }
+
+    fn handle_modifiers_changed(
+        &mut self,
+        event: &ModifiersChangedEvent,
+        window: &mut gpui::Window,
+        cx: &mut Context<Self>,
+    ) {
+        let Some(init_modifiers) = self.init_modifiers else {
+            return;
+        };
+        if !event.modified() || !init_modifiers.is_subset_of(event) {
+            self.init_modifiers = None;
+            if self.entries.is_empty() {
+                cx.emit(DismissEvent);
+            } else {
+                window.dispatch_action(menu::Confirm.boxed_clone(), cx);
+            }
+        }
+    }
+}
+
+impl ModalView for ThreadSwitcher {}
+
+impl EventEmitter<DismissEvent> for ThreadSwitcher {}
+impl EventEmitter<ThreadSwitcherEvent> for ThreadSwitcher {}
+
+impl Focusable for ThreadSwitcher {
+    fn focus_handle(&self, _cx: &gpui::App) -> FocusHandle {
+        self.focus_handle.clone()
+    }
+}
+
+impl Render for ThreadSwitcher {
+    fn render(&mut self, _window: &mut gpui::Window, cx: &mut Context<Self>) -> impl IntoElement {
+        let selected_index = self.selected_index;
+        let color = cx.theme().colors();
+        let panel_bg = color
+            .title_bar_background
+            .blend(color.panel_background.opacity(0.2));
+
+        v_flex()
+            .key_context("ThreadSwitcher")
+            .track_focus(&self.focus_handle)
+            .w(gpui::rems(PANEL_WIDTH_REMS))
+            .elevation_3(cx)
+            .on_modifiers_changed(cx.listener(Self::handle_modifiers_changed))
+            .on_action(cx.listener(Self::confirm))
+            .on_action(cx.listener(Self::cancel))
+            .on_action(cx.listener(Self::toggle))
+            .children(self.entries.iter().enumerate().map(|(ix, entry)| {
+                let is_first = ix == 0;
+                let is_last = ix == self.entries.len() - 1;
+                let selected = ix == selected_index;
+                let base_bg = if selected {
+                    color.element_active
+                } else {
+                    panel_bg
+                };
+
+                let dot_separator = || {
+                    Label::new("\u{2022}")
+                        .size(LabelSize::Small)
+                        .color(Color::Muted)
+                        .alpha(0.5)
+                };
+
+                let icon_container = || h_flex().size_4().flex_none().justify_center();
+
+                let agent_icon = || {
+                    if let Some(ref svg) = entry.icon_from_external_svg {
+                        Icon::from_external_svg(svg.clone())
+                            .color(Color::Muted)
+                            .size(IconSize::Small)
+                    } else {
+                        Icon::new(entry.icon)
+                            .color(Color::Muted)
+                            .size(IconSize::Small)
+                    }
+                };
+
+                let decoration = |kind: IconDecorationKind, deco_color: Hsla| {
+                    IconDecoration::new(kind, base_bg, cx)
+                        .color(deco_color)
+                        .position(gpui::Point {
+                            x: px(-2.),
+                            y: px(-2.),
+                        })
+                };
+
+                let icon_element: AnyElement = if entry.status == AgentThreadStatus::Running {
+                    icon_container()
+                        .child(
+                            Icon::new(IconName::LoadCircle)
+                                .size(IconSize::Small)
+                                .color(Color::Muted)
+                                .with_rotate_animation(2),
+                        )
+                        .into_any_element()
+                } else if entry.status == AgentThreadStatus::Error {
+                    icon_container()
+                        .child(DecoratedIcon::new(
+                            agent_icon(),
+                            Some(decoration(IconDecorationKind::X, cx.theme().status().error)),
+                        ))
+                        .into_any_element()
+                } else if entry.status == AgentThreadStatus::WaitingForConfirmation {
+                    icon_container()
+                        .child(DecoratedIcon::new(
+                            agent_icon(),
+                            Some(decoration(
+                                IconDecorationKind::Triangle,
+                                cx.theme().status().warning,
+                            )),
+                        ))
+                        .into_any_element()
+                } else if entry.notified {
+                    icon_container()
+                        .child(DecoratedIcon::new(
+                            agent_icon(),
+                            Some(decoration(IconDecorationKind::Dot, color.text_accent)),
+                        ))
+                        .into_any_element()
+                } else {
+                    icon_container().child(agent_icon()).into_any_element()
+                };
+
+                let title_label: AnyElement = if entry.is_title_generating {
+                    Label::new(entry.title.clone())
+                        .color(Color::Muted)
+                        .with_animation(
+                            "generating-title",
+                            Animation::new(Duration::from_secs(2))
+                                .repeat()
+                                .with_easing(pulsating_between(0.4, 0.8)),
+                            |label, delta| label.alpha(delta),
+                        )
+                        .into_any_element()
+                } else {
+                    Label::new(entry.title.clone()).into_any_element()
+                };
+
+                let has_diff_stats =
+                    entry.diff_stats.lines_added > 0 || entry.diff_stats.lines_removed > 0;
+                let has_worktree = entry.worktree_name.is_some();
+                let has_timestamp = !entry.timestamp.is_empty();
+
+                v_flex()
+                    .id(ix)
+                    .w_full()
+                    .py_1()
+                    .px_1p5()
+                    .border_1()
+                    .border_color(gpui::transparent_black())
+                    .when(selected, |s| s.bg(color.element_active))
+                    .when(is_first, |s| s.rounded_t_lg())
+                    .when(is_last, |s| s.rounded_b_lg())
+                    .child(
+                        h_flex()
+                            .min_w_0()
+                            .w_full()
+                            .gap_1p5()
+                            .child(icon_element)
+                            .child(title_label),
+                    )
+                    .when(has_worktree || has_diff_stats || has_timestamp, |this| {
+                        this.child(
+                            h_flex()
+                                .min_w_0()
+                                .gap_1p5()
+                                .child(icon_container())
+                                .when_some(entry.worktree_name.clone(), |this, worktree| {
+                                    this.child(
+                                        h_flex()
+                                            .gap_1()
+                                            .child(
+                                                Icon::new(IconName::GitWorktree)
+                                                    .size(IconSize::XSmall)
+                                                    .color(Color::Muted),
+                                            )
+                                            .child(
+                                                Label::new(worktree)
+                                                    .size(LabelSize::Small)
+                                                    .color(Color::Muted),
+                                            ),
+                                    )
+                                })
+                                .when(has_worktree && (has_diff_stats || has_timestamp), |this| {
+                                    this.child(dot_separator())
+                                })
+                                .when(has_diff_stats, |this| {
+                                    this.child(DiffStat::new(
+                                        ix,
+                                        entry.diff_stats.lines_added as usize,
+                                        entry.diff_stats.lines_removed as usize,
+                                    ))
+                                })
+                                .when(has_diff_stats && has_timestamp, |this| {
+                                    this.child(dot_separator())
+                                })
+                                .when(has_timestamp, |this| {
+                                    this.child(
+                                        Label::new(entry.timestamp.clone())
+                                            .size(LabelSize::Small)
+                                            .color(Color::Muted),
+                                    )
+                                }),
+                        )
+                    })
+            }))
+    }
+}

crates/title_bar/src/title_bar.rs 🔗

@@ -49,6 +49,7 @@ use util::ResultExt;
 use workspace::{
     MultiWorkspace, ToggleWorktreeSecurity, Workspace, WorkspaceId, notifications::NotifyResultExt,
 };
+
 use zed_actions::OpenRemote;
 
 pub use onboarding_banner::restore_banner;

crates/workspace/src/multi_workspace.rs 🔗

@@ -15,7 +15,7 @@ use std::path::PathBuf;
 use std::sync::Arc;
 use ui::prelude::*;
 use util::ResultExt;
-use zed_actions::agents_sidebar::MoveWorkspaceToNewWindow;
+use zed_actions::agents_sidebar::{MoveWorkspaceToNewWindow, ToggleThreadSwitcher};
 
 use agent_settings::AgentSettings;
 use settings::SidebarDockPosition;
@@ -100,8 +100,16 @@ pub trait Sidebar: Focusable + Render + Sized {
     fn is_threads_list_view_active(&self) -> bool {
         true
     }
-    /// Makes focus reset bac to the search editor upon toggling the sidebar from outside
+    /// Makes focus reset back to the search editor upon toggling the sidebar from outside
     fn prepare_for_focus(&mut self, _window: &mut Window, _cx: &mut Context<Self>) {}
+    /// Opens or cycles the thread switcher popup.
+    fn toggle_thread_switcher(
+        &mut self,
+        _select_last: bool,
+        _window: &mut Window,
+        _cx: &mut Context<Self>,
+    ) {
+    }
 }
 
 pub trait SidebarHandle: 'static + Send + Sync {
@@ -113,6 +121,7 @@ pub trait SidebarHandle: 'static + Send + Sync {
     fn has_notifications(&self, cx: &App) -> bool;
     fn to_any(&self) -> AnyView;
     fn entity_id(&self) -> EntityId;
+    fn toggle_thread_switcher(&self, select_last: bool, window: &mut Window, cx: &mut App);
 
     fn is_threads_list_view_active(&self, cx: &App) -> bool;
 
@@ -162,6 +171,15 @@ impl<T: Sidebar> SidebarHandle for Entity<T> {
         Entity::entity_id(self)
     }
 
+    fn toggle_thread_switcher(&self, select_last: bool, window: &mut Window, cx: &mut App) {
+        let entity = self.clone();
+        window.defer(cx, move |window, cx| {
+            entity.update(cx, |this, cx| {
+                this.toggle_thread_switcher(select_last, window, cx);
+            });
+        });
+    }
+
     fn is_threads_list_view_active(&self, cx: &App) -> bool {
         self.read(cx).is_threads_list_view_active()
     }
@@ -177,6 +195,7 @@ pub struct MultiWorkspace {
     active_workspace_index: usize,
     sidebar: Option<Box<dyn SidebarHandle>>,
     sidebar_open: bool,
+    sidebar_overlay: Option<AnyView>,
     pending_removal_tasks: Vec<Task<()>>,
     _serialize_task: Option<Task<()>>,
     _subscriptions: Vec<Subscription>,
@@ -225,6 +244,7 @@ impl MultiWorkspace {
             active_workspace_index: 0,
             sidebar: None,
             sidebar_open: false,
+            sidebar_overlay: None,
             pending_removal_tasks: Vec::new(),
             _serialize_task: None,
             _subscriptions: vec![
@@ -247,6 +267,11 @@ impl MultiWorkspace {
         self.sidebar.as_deref()
     }
 
+    pub fn set_sidebar_overlay(&mut self, overlay: Option<AnyView>, cx: &mut Context<Self>) {
+        self.sidebar_overlay = overlay;
+        cx.notify();
+    }
+
     pub fn sidebar_open(&self) -> bool {
         self.sidebar_open
     }
@@ -916,6 +941,13 @@ impl Render for MultiWorkspace {
                     .on_action(cx.listener(Self::next_workspace))
                     .on_action(cx.listener(Self::previous_workspace))
                     .on_action(cx.listener(Self::move_active_workspace_to_new_window))
+                    .on_action(cx.listener(
+                        |this: &mut Self, action: &ToggleThreadSwitcher, window, cx| {
+                            if let Some(sidebar) = &this.sidebar {
+                                sidebar.toggle_thread_switcher(action.select_last, window, cx);
+                            }
+                        },
+                    ))
                 })
                 .when(
                     self.sidebar_open() && self.multi_workspace_enabled(cx),
@@ -947,7 +979,20 @@ impl Render for MultiWorkspace {
                         .child(self.workspace().clone()),
                 )
                 .children(right_sidebar)
-                .child(self.workspace().read(cx).modal_layer.clone()),
+                .child(self.workspace().read(cx).modal_layer.clone())
+                .children(self.sidebar_overlay.as_ref().map(|view| {
+                    deferred(div().absolute().size_full().inset_0().occlude().child(
+                        v_flex().h(px(0.0)).top_20().items_center().child(
+                            h_flex().occlude().child(view.clone()).on_mouse_down(
+                                MouseButton::Left,
+                                |_, _, cx| {
+                                    cx.stop_propagation();
+                                },
+                            ),
+                        ),
+                    ))
+                    .with_priority(2)
+                })),
             window,
             cx,
             Tiling {

crates/zed_actions/src/lib.rs 🔗

@@ -779,7 +779,18 @@ pub mod preview {
 }
 
 pub mod agents_sidebar {
-    use gpui::actions;
+    use gpui::{Action, actions};
+    use schemars::JsonSchema;
+    use serde::Deserialize;
+
+    /// Toggles the thread switcher popup when the sidebar is focused.
+    #[derive(PartialEq, Clone, Deserialize, JsonSchema, Default, Action)]
+    #[action(namespace = agents_sidebar)]
+    #[serde(deny_unknown_fields)]
+    pub struct ToggleThreadSwitcher {
+        #[serde(default)]
+        pub select_last: bool,
+    }
 
     actions!(
         agents_sidebar,