diff --git a/CHANGELOG.md b/CHANGELOG.md
index 495e7a7d..915bf4a1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -64,6 +64,14 @@ Status of the `main` branch. Changes prior to the next official version change w
     successful Serena call. Add a `serena-hooks reset` command and a `PostToolUse` example matched to
     Serena's own tools to close the gap (#1852)
 
+* Dashboard:
+  - Fix: On macOS, the tray manager refreshed the tray menu straight from the Flask request handlers
+    for `/register`, `/update_project` and `/unregister` and from the alive-check thread. That reaches
+    `NSStatusItem.setMenu_()` off the main thread, which AppKit forbids and which recent macOS
+    versions punish with SIGTRAP, so the tray-manager process died within seconds of every agent
+    start and the tray icon never became usable. Menu refreshes are now marshalled onto the main
+    thread (#2038)
+
 * Language Servers:
   - Fix: Godot's GDScript parser can report a symbol's end column one column past the
     line-end convention every other language server follows (closing a node's range from
diff --git a/src/serena/dashboard.py b/src/serena/dashboard.py
index 4d0574b8..e186117c 100644
--- a/src/serena/dashboard.py
+++ b/src/serena/dashboard.py
@@ -1030,9 +1030,28 @@ class SerenaDashboardTrayManager:
             log.info("Unregistered instance on port %d", port)
             return {"status": "unregistered"}
 
+    @staticmethod
+    def _run_in_ui_thread(fn: Callable[[], None]) -> None:
+        """
+        Runs a UI mutation in the thread in which the platform's UI toolkit requires it to run.
+
+        On macOS, AppKit demands that mutations of the status item happen on the main thread, and
+        recent macOS versions terminate the process with SIGTRAP when they do not. The tray manager
+        reaches such mutations from Flask request handlers and from the alive-check thread, so the
+        call has to be marshalled. On other platforms it is made directly.
+
+        :param fn: the UI mutation to run
+        """
+        if sys.platform == "darwin":
+            from PyObjCTools import AppHelper
+
+            AppHelper.callAfter(fn)
+        else:
+            fn()
+
     def _update_menu(self) -> None:
         if self._tray_icon:
-            self._tray_icon.update_menu()
+            self._run_in_ui_thread(self._tray_icon.update_menu)
 
     def _build_menu_items(self) -> tuple[Any, ...]:
         """