[Settings] Speed up page navigation; fix Advanced Paste double-load

src/settings-ui/Settings.UI/Helpers/NavigablePage.cs

@@ -10,6 +10,7 @@
 using Microsoft.UI.Xaml.Controls;
 using Microsoft.UI.Xaml.Hosting;
 using Microsoft.UI.Xaml.Media;
+using Microsoft.UI.Xaml.Navigation;
 using Windows.UI;
 
 namespace Microsoft.PowerToys.Settings.UI.Helpers;
@@ -23,6 +24,10 @@ public abstract partial class NavigablePage : Page
 
     public NavigablePage()
     {
+        // Cache the page instance so re-navigating doesn't rebuild the XAML tree, ViewModel,
+        // file watchers and IPC handlers each time. The Frame's default CacheSize (10) is
+        // sufficient to keep all top-level settings pages warm.
+        NavigationCacheMode = NavigationCacheMode.Enabled;
         Loaded += OnPageLoaded;
     }
 

src/settings-ui/Settings.UI/SettingsXAML/App.xaml

@@ -90,10 +90,9 @@
             <tkcontrols:MarkdownConfig x:Key="DescriptionTextMarkdownConfig" Themes="{StaticResource DescriptionTextMarkdownThemeConfig}" />
 
             <TransitionCollection x:Key="SettingsCardsAnimations">
-                <EntranceThemeTransition FromVerticalOffset="50" />
-                <!--  Animates cards when loaded  -->
                 <RepositionThemeTransition IsStaggeringEnabled="False" />
                 <!--  Smoothly animates individual cards upon whenever Expanders are expanded/collapsed  -->
+                <!--  EntranceThemeTransition removed: it replayed on every page navigation, causing a visible "second load" reflow and slowing perceived nav.  -->
             </TransitionCollection>
         </ResourceDictionary>
     </Application.Resources>

src/settings-ui/Settings.UI/SettingsXAML/Views/AdvancedPastePage.xaml.cs

@@ -30,6 +30,7 @@ public sealed partial class AdvancedPastePage : NavigablePage, IRefreshablePage,
         private CancellationTokenSource _foundryModelLoadCts;
         private bool _suppressFoundrySelectionChanged;
         private bool _isFoundryLocalAvailable;
+        private bool _isPasteAIProviderDialogOpen;
         private bool _disposed;
         private const string PasteAiDialogDefaultTitle = "Paste with AI provider configuration";
 
@@ -60,11 +61,16 @@ public AdvancedPastePage()
                 FoundryLocalPicker.LoadRequested += FoundryLocalPicker_LoadRequested;
             }
 
-            Loaded += async (s, e) =>
+            Loaded += (s, e) =>
             {
                 ViewModel.OnPageLoaded();
-                UpdatePasteAIUIVisibility();
-                await UpdateFoundryLocalUIAsync();
+
+                // Note: UpdatePasteAIUIVisibility() and UpdateFoundryLocalUIAsync() are deliberately
+                // NOT called here. They only affect controls inside PasteAIProviderConfigurationDialog,
+                // which is hidden until the user clicks Add/Edit provider. Both Add/Edit handlers call
+                // them right before ShowAsync(), so running them on every navigation is wasted work
+                // that produced a visible second reflow ("double load") and, for FoundryLocal, an
+                // unnecessary process probe.
             };
 
             Unloaded += (_, _) =>
@@ -81,8 +87,15 @@ public AdvancedPastePage()
         public void RefreshEnabledState()
         {
             ViewModel.RefreshEnabledState();
-            UpdatePasteAIUIVisibility();
-            _ = UpdateFoundryLocalUIAsync();
+
+            // Only refresh the provider-configuration dialog state if it is currently open;
+            // otherwise this is wasted work (and, for FoundryLocal, an unnecessary process probe)
+            // that fires every time the runner broadcasts a general-settings update.
+            if (_isPasteAIProviderDialogOpen)
+            {
+                UpdatePasteAIUIVisibility();
+                _ = UpdateFoundryLocalUIAsync();
+            }
         }
 
         private void EnableAdvancedPasteAI() => ViewModel.EnableAI();
@@ -1116,6 +1129,7 @@ private async void ProviderMenuFlyoutItem_Click(object sender, RoutedEventArgs e
             RefreshDialogBindings();
 
             PasteAIApiKeyPasswordBox.Password = string.Empty;
+            _isPasteAIProviderDialogOpen = true;
             await PasteAIProviderConfigurationDialog.ShowAsync();
         }
 
@@ -1143,6 +1157,7 @@ private async void EditPasteAIProviderButton_Click(object sender, RoutedEventArg
             await UpdateFoundryLocalUIAsync();
             RefreshDialogBindings();
             PasteAIApiKeyPasswordBox.Password = ViewModel.GetPasteAIApiKey(provider.Id, provider.ServiceType);
+            _isPasteAIProviderDialogOpen = true;
             await PasteAIProviderConfigurationDialog.ShowAsync();
         }
 
@@ -1159,6 +1174,7 @@ private void RemovePasteAIProviderButton_Click(object sender, RoutedEventArgs e)
 
         private void PasteAIProviderConfigurationDialog_Closed(ContentDialog sender, ContentDialogClosedEventArgs args)
         {
+            _isPasteAIProviderDialogOpen = false;
             ViewModel?.CancelPasteAIProviderDraft();
             PasteAIProviderConfigurationDialog.Title = PasteAiDialogDefaultTitle;
             PasteAIApiKeyPasswordBox.Password = string.Empty;