diff --git a/components/remote_cocoa/app_shim/select_file_dialog_bridge.mm b/components/remote_cocoa/app_shim/select_file_dialog_bridge.mm
index 6531f80a40c67..10171bf3d41c6 100644
--- a/components/remote_cocoa/app_shim/select_file_dialog_bridge.mm
+++ b/components/remote_cocoa/app_shim/select_file_dialog_bridge.mm
@@ -427,9 +427,14 @@ void SelectFileDialogBridge::Show(
       open_dialog.canChooseDirectories = NO;
     }
 
-    delegate_ = [[SelectFileDialogDelegate alloc] init];
-    open_dialog.delegate = delegate_;
   }
+
+  // Install the delegate on |panel_| for both the open *and* save cases so
+  // that -panel:validateURL:error: vetoes auto-repeated key events
+  // (https://crbug.com/40085079) on NSSavePanel as well as NSOpenPanel.
+  delegate_ = [[SelectFileDialogDelegate alloc] init];
+  panel_.delegate = delegate_;
+
   if (default_dir) {
     panel_.directoryURL = [NSURL fileURLWithPath:default_dir];
   }