diff --git a/frontends/tuiapp_v2.py b/frontends/tuiapp_v2.py
index 8e37ec7f5..9bc5fc959 100644
--- a/frontends/tuiapp_v2.py
+++ b/frontends/tuiapp_v2.py
@@ -29,7 +29,7 @@
 from keysym import fmt_key, fmt_keys  # noqa: E402
 from dataclasses import dataclass, field
 from itertools import count
-from typing import Any, Callable, Optional
+from typing import Any, Callable, List, Optional
 
 
 def _ensure_tui_deps() -> None:
@@ -6591,9 +6591,13 @@ def _on_stream(self, agent_id, task_id, text, done):
                         except Exception: self._refresh_messages()
                     else:
                         self._refresh_messages()
-                    if refresh_chrome:
-                        self._refresh_sidebar()
-                        self._refresh_topbar()
+                    # Mirror the regular done=True path below (line ~6603) which
+                    # always refreshes sidebar+topbar on completion. The replay
+                    # path used to reference an undefined `refresh_chrome` local
+                    # (NameError on every exit-boundary replay); the agent is
+                    # in fact done, so always refresh chrome here.
+                    self._refresh_sidebar()
+                    self._refresh_topbar()
                     self._ensure_spinner()
             return
         s.buffer = text
diff --git a/test_issue_6594_tui_v2_stale_replay_nameerror.py b/test_issue_6594_tui_v2_stale_replay_nameerror.py
new file mode 100644
index 000000000..5d0ca979a
--- /dev/null
+++ b/test_issue_6594_tui_v2_stale_replay_nameerror.py
@@ -0,0 +1,127 @@
+"""Regression test for frontends/tuiapp_v2.py:6594 NameError on the
+exit-boundary replay path.
+
+Background
+----------
+`_on_stream(self, agent_id, task_id, text, done)` is invoked from
+`_consume_display_queue` (a worker thread) via `call_from_thread`. The
+function does NOT accept a `refresh_chrome` parameter, but its stale-replay
+branch (when `s.current_task_id != task_id`) referenced `refresh_chrome` —
+triggering `NameError: name 'refresh_chrome' is not defined` whenever an
+exit-boundary replay settled an old assistant message.
+
+The regular `done=True` path (line ~6603) handles the same situation by
+always calling `_refresh_sidebar` + `_refresh_topbar`, so the fix mirrors
+that.
+
+Repro
+-----
+Construct a minimal `GenericAgentTUI` instance with a fake session whose
+`current_task_id` is newer than the incoming `task_id` and call
+`_on_stream(... task_id=old, done=True)`. Before the fix this raises
+`NameError`; after the fix it returns cleanly and calls the three refresh
+methods.
+"""
+from __future__ import annotations
+
+import sys
+import os
+import importlib.util
+import pathlib
+import types
+import unittest
+
+ROOT = pathlib.Path(__file__).resolve().parent
+sys.path.insert(0, str(ROOT))                 # for `keysym`
+sys.path.insert(0, str(ROOT / "frontends"))   # for `tuiapp_v2`
+
+# Pre-import the textual/rich/keysym deps so spec.loader.exec_module() doesn't
+# fall into the auto-install fallback (it requires network + write perms).
+import textual  # noqa: F401
+import rich  # noqa: F401
+import keysym  # noqa: F401
+
+
+def _load_module():
+    spec = importlib.util.spec_from_file_location(
+        "tuiapp_v2_under_test", ROOT / "frontends" / "tuiapp_v2.py"
+    )
+    mod = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = mod
+    spec.loader.exec_module(mod)
+    return mod
+
+
+class StaleReplayNameErrorRepro(unittest.TestCase):
+    def setUp(self) -> None:
+        self.m = _load_module()
+        self.app = self.m.GenericAgentTUI.__new__(self.m.GenericAgentTUI)
+        # Minimal session state for the stale-replay branch.
+        sess = types.SimpleNamespace()
+        sess.agent = None
+        sess.current_task_id = 99  # the new (replay owner's) task
+        sess.messages = []
+        sess.status = "idle"
+        msg = types.SimpleNamespace(
+            role="assistant",
+            content="",
+            done=False,
+            task_id=42,            # the OLD task being settled
+            _segment_widgets=None,
+        )
+        sess.messages.append(msg)
+        self.app.sessions = {"s1": sess}
+        self.app.current_id = "s1"
+
+        # Counters for each refresh callback.
+        self.calls = {
+            "stream_update": 0,
+            "refresh_messages": 0,
+            "refresh_sidebar": 0,
+            "refresh_topbar": 0,
+            "ensure_spinner": 0,
+        }
+
+        def make(name):
+            def _cb(*_a, **_k):
+                self.calls[name] += 1
+            _cb.__name__ = name
+            return _cb
+
+        self.app._stream_update_assistant = make("stream_update")
+        self.app._refresh_messages = make("refresh_messages")
+        self.app._refresh_sidebar = make("refresh_sidebar")
+        self.app._refresh_topbar = make("refresh_topbar")
+        self.app._ensure_spinner = make("ensure_spinner")
+
+    def test_replay_path_runs_without_name_error(self) -> None:
+        """Pre-fix this raises NameError; post-fix it returns cleanly."""
+        try:
+            self.app._on_stream("s1", 42, "final text", done=True)
+        except NameError as exc:
+            self.fail(f"Replay path raised NameError: {exc}")
+        # Old assistant message must be marked done.
+        msg = self.app.sessions["s1"].messages[0]
+        self.assertTrue(msg.done, "old assistant message should be settled")
+        self.assertEqual(msg.content, "final text")
+        # Sidebar + topbar must refresh on settle, mirror the regular path.
+        self.assertEqual(self.calls["refresh_sidebar"], 1)
+        self.assertEqual(self.calls["refresh_topbar"], 1)
+        self.assertEqual(self.calls["ensure_spinner"], 1)
+        # messages refresh: 1 from the empty-_segment_widgets branch.
+        self.assertEqual(self.calls["refresh_messages"], 1)
+        # stream_update: not used (no widgets).
+        self.assertEqual(self.calls["stream_update"], 0)
+
+    def test_done_false_is_a_noop(self) -> None:
+        """The replay path is gated on `done=True`; done=False must skip everything."""
+        self.app._on_stream("s1", 42, "intermediate", done=False)
+        for k, v in self.calls.items():
+            self.assertEqual(v, 0, f"{k} should be 0 on done=False, got {v}")
+        # The message is NOT marked done when done=False.
+        msg = self.app.sessions["s1"].messages[0]
+        self.assertFalse(msg.done)
+
+
+if __name__ == "__main__":
+    unittest.main()