fix: recover PWA after backgrounding

second_spawn_on_same_branch_is_rejected asserted the same pre-#77
outright-rejection contract as the unit test fixed in 0e20baf, just at
the e2e/session level — also broken by 49ab7e9's branch-collision
suffixing and also already failing on main.

Renamed to second_spawn_on_same_branch_gets_suffixed and rewritten to
assert the actual behavior: the second spawn succeeds on a `-2`
suffixed branch and directory, and the first worktree is untouched.

crates/maestro-daemon/tests/worktree.rs

@@ -405,13 +405,17 @@ fn run_git(dir: &std::path::Path, args: &[&str]) {
     );
 }
 
+/// `git worktree add -b` alone fails outright when the branch already exists,
+/// even with the target directory free — a random handle commonly collides
+/// with one an earlier, already-removed worktree left behind. `add_new`
+/// sidesteps it on the branch name itself instead of erroring (#77).
 #[test]
-fn add_fails_when_branch_already_exists() {
+fn add_new_suffixes_branch_name_on_branch_collision() {
     let repo_dir = TempDir::new().unwrap();
     let repo = repo_dir.path().to_path_buf();
     init_repo(&repo);
 
-    // pre-create the branch
+    // pre-create the branch, unused by any worktree.
     let status = Command::new("git")
         .arg("-C")
         .arg(&repo)
@@ -423,9 +427,17 @@ fn add_fails_when_branch_already_exists() {
     let wt_root = TempDir::new().unwrap();
     let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));
 
-    let err = mgr.add_new(&repo, "feat/dup").unwrap_err();
-    let msg = format!("{err}");
-    assert!(msg.contains("git exited"), "{msg}");
+    let path = mgr
+        .add_new(&repo, "feat/dup")
+        .expect("sidesteps the branch collision");
+    assert!(path.ends_with("feat/dup-2"), "{}", path.display());
+    assert!(path.exists());
+
+    // The pre-existing branch is untouched; the new worktree checked out the
+    // suffixed one instead of erroring or adopting `feat/dup`.
+    let branches = worktree_branches(&repo);
+    assert!(branches.contains(&"feat/dup-2".to_string()), "{branches:?}");
+    assert!(!branches.contains(&"feat/dup".to_string()), "{branches:?}");
 }
 
 /// The project picker lists linked worktrees as pickable rows, so `base_repo`

crates/maestro-e2e/tests/e2e.rs

@@ -323,10 +323,11 @@ async fn spawn_new_branch_creates_worktree_and_runs_in_it() {
     client.kill_session(s.id).await.expect("kill");
 }
 
-/// #66: a second spawn onto a branch that already has a worktree is rejected
-/// with a structured worktree error; the first worktree stays intact.
+/// #66/#77: a second spawn onto the same branch used to be rejected outright;
+/// since the branch-collision suffixing landed, it succeeds instead — the
+/// second worktree lands on `<branch>-2` and the first stays untouched.
 #[tokio::test(flavor = "multi_thread")]
-async fn second_spawn_on_same_branch_is_rejected() {
+async fn second_spawn_on_same_branch_gets_suffixed() {
     let (_daemon, client) = bring_up().await;
 
     let base = TempDir::new().unwrap();
@@ -336,28 +337,33 @@ async fn second_spawn_on_same_branch_is_rejected() {
         .spawn_session(&worktree_req(base.path(), "feature/dup", true))
         .await
         .expect("first spawn");
-    let dup = client
+    let second = client
         .spawn_session(&worktree_req(base.path(), "feature/dup", true))
-        .await;
-    match dup {
-        Err(maestro_e2e::ClientError::Api(maestro_protocol::ClientError::Api { info, .. })) => {
-            assert_eq!(
-                info.code, "worktree_failed",
-                "expected worktree error: {info:?}"
-            );
-        }
-        other => panic!("expected rejection for duplicate branch, got {other:?}"),
-    }
+        .await
+        .expect("second spawn suffixes instead of rejecting");
 
-    // Exactly one registration, one directory, still usable.
-    // Count branch records only: the worktree path now contains the branch
-    // name too (`worktrees/feature/dup`), so a substring match over every line
-    // would count the same tree twice.
-    let holders = git_worktree_list(base.path())
-        .iter()
-        .filter(|w| w.as_str() == "branch refs/heads/feature/dup")
-        .count();
-    assert_eq!(holders, 1, "duplicate spawn must not register another tree");
+    let suffixed = base.path().join("worktrees").join("feature").join("dup-2");
+    assert_eq!(
+        second.cwd, suffixed,
+        "second worktree must land on the suffixed path"
+    );
+    assert!(suffixed.is_dir());
+
+    // Both registrations exist: the original branch, untouched, and the
+    // suffixed one the second spawn created.
+    let registrations = git_worktree_list(base.path());
+    assert!(
+        registrations
+            .iter()
+            .any(|l| l.as_str() == "branch refs/heads/feature/dup"),
+        "original branch must stay registered: {registrations:?}"
+    );
+    assert!(
+        registrations
+            .iter()
+            .any(|l| l.as_str() == "branch refs/heads/feature/dup-2"),
+        "suffixed branch must be registered too: {registrations:?}"
+    );
     assert!(
         base.path()
             .join("worktrees")
@@ -368,7 +374,8 @@ async fn second_spawn_on_same_branch_is_rejected() {
     );
 
     let _origin = throwaway_origin(base.path());
-    client.kill_session(first.id).await.expect("kill");
+    client.kill_session(first.id).await.expect("kill first");
+    client.kill_session(second.id).await.expect("kill second");
 }
 
 /// #66/#56: when the client picks a *linked worktree* as base_repo, placement

web/src/attach.ts

@@ -367,6 +367,9 @@ export function createAttachConnection(
   let ws: WebSocket;
   let reconnectMs = INITIAL_RECONNECT_MS;
   let reconnectTimer: number | null = null;
+  // Snapshot replay starts at row zero, which can leave Codex at its oldest line.
+  // Follow it once per socket; later scrolling remains under the operator's control.
+  let awaitingReplay = true;
 
   const sendControl = (msg: ClientControl) => {
     if (ws.readyState !== WebSocket.OPEN) return;
@@ -386,6 +389,7 @@ export function createAttachConnection(
   };
 
   function connect(): void {
+    awaitingReplay = true;
     ws = new WebSocket(attachWsUrl(sessionId));
     ws.binaryType = "arraybuffer";
 
@@ -406,10 +410,20 @@ export function createAttachConnection(
         return;
       }
       if (ev.data instanceof ArrayBuffer) {
-        term.write(new Uint8Array(ev.data));
+        const replay = awaitingReplay;
+        awaitingReplay = false;
+        term.write(new Uint8Array(ev.data), () => {
+          if (replay) term.scrollToBottom();
+        });
       } else if (ev.data instanceof Blob) {
         // Some browsers may default to Blob despite binaryType="arraybuffer".
-        ev.data.arrayBuffer().then((b) => term.write(new Uint8Array(b)));
+        void ev.data.arrayBuffer().then((b) => {
+          const replay = awaitingReplay;
+          awaitingReplay = false;
+          term.write(new Uint8Array(b), () => {
+            if (replay) term.scrollToBottom();
+          });
+        });
       }
     };
 

web/src/daemonLink.test.ts

@@ -130,6 +130,31 @@ describe("DaemonLink", () => {
     expect(link.status().state).toBe("online");
   });
 
+  it("rechecks immediately when the browser returns from the background", async () => {
+    const sched = manual();
+    let reply: DaemonInfo | null = info("aaa", "i1");
+    const link = new DaemonLink({
+      fetchInfo: async () => {
+        if (!reply) throw new Error("down");
+        return reply;
+      },
+      scheduler: sched,
+      reload: () => {},
+    });
+    await link.start();
+
+    reply = null;
+    link.noteDisconnected();
+    sched.run();
+    await Promise.resolve();
+    expect(link.status().state).toBe("down");
+
+    reply = info("aaa", "i1");
+    link.recover();
+    await Promise.resolve();
+    expect(link.status().state).toBe("online");
+  });
+
   it("reloads the page when the daemon comes back on a new commit", async () => {
     const sched = manual();
     const reload = vi.fn();

web/src/daemonLink.ts

@@ -148,6 +148,17 @@ export class DaemonLink {
     void this.probe();
   }
 
+  /**
+   * Recheck liveness after the browser resumes from the background. Mobile
+   * browsers may suspend both WebSocket events and timers while a PWA is
+   * hidden, leaving a stale `down` state after the daemon is already back.
+   */
+  recover(): void {
+    if (this.state === "updating") return;
+    this.noteDisconnected();
+    void this.probe();
+  }
+
   /**
    * One `/api/info` round-trip. Resolves `true` when the daemon answered.
    *

web/src/events.test.ts

@@ -132,6 +132,21 @@ describe("CatalogStore reducer", () => {
 });
 
 describe("CatalogStore reconnect", () => {
+  it("replaces a suspended socket immediately", () => {
+    const first = new FakeSocket();
+    const second = new FakeSocket();
+    const { store } = storeWith([first, second]);
+    store.start();
+
+    store.reconnect();
+
+    expect(first.closed).toBe(true);
+    second.open();
+    // A late close from the old socket is deliberately ignored.
+    first.drop();
+    expect(store.backoff()).toBe(INITIAL_BACKOFF_MS);
+  });
+
   it("doubles the delay per attempt and caps it", () => {
     const sockets = Array.from({ length: 8 }, () => new FakeSocket());
     const { store, scheduler } = storeWith(sockets);

web/src/events.ts

@@ -59,6 +59,23 @@ export class CatalogStore {
     this.connect();
   }
 
+  /** Replace a socket that may have gone stale while the browser was suspended. */
+  reconnect(): void {
+    if (this.reconnectTimer !== null) {
+      this.scheduler.clearTimer(this.reconnectTimer);
+      this.reconnectTimer = null;
+    }
+    if (this.ws) {
+      // A close event from the superseded socket must not schedule a second
+      // connection alongside the new one.
+      this.ws.onclose = null;
+      this.ws.onerror = null;
+      this.ws.close();
+      this.ws = null;
+    }
+    this.connect();
+  }
+
   /** Current reconnect delay, for tests asserting the backoff schedule. */
   backoff(): number {
     return this.backoffMs;

web/src/main.ts

@@ -107,6 +107,19 @@ void link.start();
 
 store.start();
 
+// Installed mobile browsers suspend timers and WebSockets in the background.
+// Replacing the socket on return avoids leaving the restart overlay up after a
+// transient lost connection has already recovered.
+function recoverFromBackground(): void {
+  if (document.visibilityState !== "visible") return;
+  link.recover();
+  store.reconnect();
+}
+
+document.addEventListener("visibilitychange", recoverFromBackground);
+window.addEventListener("pageshow", recoverFromBackground);
+window.addEventListener("online", recoverFromBackground);
+
 // Dev-only: `?mock` seeds a representative catalog so the UI can be reviewed
 // without a running daemon. Stripped from production builds by Vite.
 if (import.meta.env.DEV && location.search.includes("mock")) {