diff --git a/apps/desktop-shell/scripts/check-config.mjs b/apps/desktop-shell/scripts/check-config.mjs
index cf10f570d..bdd7db4ec 100644
--- a/apps/desktop-shell/scripts/check-config.mjs
+++ b/apps/desktop-shell/scripts/check-config.mjs
@@ -1881,10 +1881,13 @@ if (
 }
 for (const snippet of [
   'open_desktop_host_bridge_external_url',
+  'external_url_unavailable_response',
   'desktop_external_url_from_request',
   'normalize_external_url',
   'open_normalized_desktop_external_url(app, url)',
   'desktop_external_url_request_accepts_only_safe_system_protocols',
+  '"external url unavailable"',
+  'external_url_unavailable_response_is_stable',
   'open_desktop_host_bridge_native_page',
   'desktop_native_page_url_from_request',
   'normalize_native_page_url',
diff --git a/apps/desktop-shell/src-tauri/src/host_bridge/navigation.rs b/apps/desktop-shell/src-tauri/src/host_bridge/navigation.rs
index cc4ee009a..2472d1048 100644
--- a/apps/desktop-shell/src-tauri/src/host_bridge/navigation.rs
+++ b/apps/desktop-shell/src-tauri/src/host_bridge/navigation.rs
@@ -48,10 +48,14 @@ pub(crate) fn open_desktop_host_bridge_external_url(
 
     match open_normalized_desktop_external_url(app, url) {
         Ok(()) => ok(request.id.clone(), json!(true)),
-        Err(error) => failed(request.id.clone(), "host_error", error.to_string()),
+        Err(_) => external_url_unavailable_response(request),
     }
 }
 
+fn external_url_unavailable_response(request: &HostBridgeRequest) -> HostBridgeResponse {
+    failed(request.id.clone(), "host_error", "external url unavailable")
+}
+
 pub(crate) fn open_desktop_host_bridge_native_page(
     app: &tauri::AppHandle,
     request: &HostBridgeRequest,
@@ -113,6 +117,16 @@ mod tests {
         }
     }
 
+    #[test]
+    fn external_url_unavailable_response_is_stable() {
+        let response = external_url_unavailable_response(&request("app.openExternalUrl"));
+
+        assert!(!response.ok);
+        let error = response.error.expect("external url error");
+        assert_eq!(error.code, "host_error");
+        assert_eq!(error.message, "external url unavailable");
+    }
+
     #[test]
     fn desktop_native_page_request_accepts_only_same_origin_h5_routes() {
         let route = desktop_native_page_url_from_request(&request_with_url(