fix(tauri): retry main-window lookup on Windows after SW_SHOW (#3A) (#2341)

app/src-tauri/src/lib.rs

@@ -1169,6 +1169,59 @@ fn set_main_window_hidden(hide: bool) {
     );
 }
 
+/// Look up the main `WebviewWindow`, optionally waiting briefly on Windows
+/// for the Tauri runtime to re-track the window after SW_SHOW.
+///
+/// Why this exists (OPENHUMAN-TAURI-3A): on Windows the close button routes
+/// through [`set_main_window_hidden`] which uses raw-HWND `SW_HIDE`. CEF
+/// treats the hidden host as gone and the Tauri runtime drops its
+/// `WebviewWindow` record for `"main"` until the next event-loop tick after
+/// SW_SHOW restores visibility. A tray "Show window" callback that runs
+/// `set_main_window_hidden(false)` and then immediately calls
+/// `app.get_webview_window("main")` can race the re-track step and observe
+/// `None` even though the OS window is visible — Sentry sees a
+/// `[tray] failed to show main window from menu: main window not found`
+/// warn even though, from the user's perspective, the window came back.
+///
+/// Bounded retry budget: up to 5 lookups with 10 ms between attempts (≤ 50 ms
+/// worst case). The tray menu is closed during this window, so the small
+/// blocking delay is invisible. After the budget expires the original
+/// error path still triggers, preserving the signal if the runtime never
+/// re-tracks (which would indicate a real lifecycle bug, not a race).
+///
+/// Non-Windows platforms use a single lookup — the close-to-tray flow that
+/// produces the race is Windows-specific (the macOS close button routes
+/// through `app.hide()` per PR #2049, and Linux/X11 keeps the
+/// `WebviewWindow` record across `WM_DELETE_WINDOW` handling).
+fn get_main_webview_window_with_retry(
+    app: &AppHandle<AppRuntime>,
+) -> Option<tauri::WebviewWindow<AppRuntime>> {
+    #[cfg(target_os = "windows")]
+    {
+        const ATTEMPTS: usize = 5;
+        const BACKOFF: std::time::Duration = std::time::Duration::from_millis(10);
+        for attempt in 0..ATTEMPTS {
+            if let Some(window) = app.get_webview_window("main") {
+                if attempt > 0 {
+                    log::debug!(
+                        "[show_main_window] runtime re-tracked main window after {} retries",
+                        attempt
+                    );
+                }
+                return Some(window);
+            }
+            if attempt + 1 < ATTEMPTS {
+                std::thread::sleep(BACKOFF);
+            }
+        }
+        None
+    }
+    #[cfg(not(target_os = "windows"))]
+    {
+        app.get_webview_window("main")
+    }
+}
+
 fn show_main_window(app: &AppHandle<AppRuntime>) -> Result<(), String> {
     // On Windows: surface the OS top-level Chrome_WidgetWin_1 frame BEFORE
     // any Tauri lookups. After our close handler's SW_HIDE the runtime
@@ -1177,7 +1230,10 @@ fn show_main_window(app: &AppHandle<AppRuntime>) -> Result<(), String> {
     // and the early `?` below would abort before SW_SHOW fires (#1607).
     // EnumWindows + SW_SHOW operates directly on the OS HWND that
     // survived independently, and the runtime re-tracks the window once
-    // it's visible again.
+    // it's visible again — but re-tracking lands on the next event-loop
+    // tick, not synchronously with SW_SHOW. `get_main_webview_window_with_retry`
+    // bounds the wait to ~50 ms total so the tray callback can pick up the
+    // re-tracked window without re-emitting OPENHUMAN-TAURI-3A.
     #[cfg(target_os = "windows")]
     {
         set_main_window_hidden(false);
@@ -1186,8 +1242,7 @@ fn show_main_window(app: &AppHandle<AppRuntime>) -> Result<(), String> {
             let _ = webview.set_focus();
         }
     }
-    let window = app
-        .get_webview_window("main")
+    let window = get_main_webview_window_with_retry(app)
         .ok_or_else(|| "main window not found".to_string())?;
     window
         .show()