Ensured the search box is focused when the dialog is opened.

source/ProjectFilter/UI/AttachedProperties/FocusWhenVisible.cs

@@ -0,0 +1,71 @@
+using Microsoft.VisualStudio;
+using System;
+using System.Windows;
+
+
+namespace ProjectFilter.UI.AttachedProperties {
+
+    public static class FocusWhenVisible {
+
+        public static readonly DependencyProperty EnabledProperty = DependencyProperty.RegisterAttached(
+            "Enabled",
+            typeof(bool),
+            typeof(FocusWhenVisible),
+            new PropertyMetadata(false, OnEnabledChanged)
+        );
+
+
+        public static bool GetEnabled(DependencyObject obj) {
+            if (obj is null) {
+                throw new ArgumentNullException(nameof(obj));
+            }
+
+            return (bool)obj.GetValue(EnabledProperty);
+        }
+
+
+        public static void SetEnabled(DependencyObject obj, bool value) {
+            if (obj is null) {
+                throw new ArgumentNullException(nameof(obj));
+            }
+
+            obj.SetValue(EnabledProperty, value);
+        }
+
+
+        private static void OnEnabledChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) {
+            UIElement? target;
+
+
+            target = d as UIElement;
+
+            if (target != null) {
+                if ((bool)e.OldValue) {
+                    target.IsVisibleChanged -= OnIsVisibleChanged;
+                }
+
+                if ((bool)e.NewValue) {
+                    target.IsVisibleChanged += OnIsVisibleChanged;
+                }
+            }
+        }
+
+
+        private static void OnIsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e) {
+            UIElement? target;
+
+
+            target = sender as UIElement;
+
+            if (target != null && target.IsVisible) {
+                try {
+                    target.Focus();
+                } catch (Exception ex) when (!ErrorHandler.IsCriticalException(ex)) {
+                    System.Diagnostics.Debug.WriteLine(ex);
+                }
+            }
+        }
+
+    }
+
+}

source/ProjectFilter/UI/FilterDialog.xaml

@@ -54,7 +54,7 @@
                 Foreground="{DynamicResource {x:Static platform:ThemedDialogColors.HeaderTextBrushKey}}"
                 />
         </Grid>
-        
+
         <Grid Visibility="{Binding LoadedVisibility}">
             <Grid.RowDefinitions>
                 <RowDefinition Height="Auto"/>
@@ -130,6 +130,7 @@
                     Style="{StaticResource SearchTextBoxStyle}"
                     properties:Watermark.Text="Filter projects..."
                     properties:ClearOnEscape.Enabled="True"
+                    properties:FocusWhenVisible.Enabled="True"
                     />
             </StackPanel>