diff --git a/AddInManager/App.config b/AddInManager/App.config
new file mode 100644
index 0000000..26e0202
--- /dev/null
+++ b/AddInManager/App.config
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<configuration>
+    <configSections>
+        <sectionGroup name="userSettings" type="System.Configuration.UserSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
+            <section name="RevitAddinManager.Properties.App" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" allowExeDefinition="MachineToLocalUser" requirePermission="false" />
+        </sectionGroup>
+    </configSections>
+    <userSettings>
+        <RevitAddinManager.Properties.App>
+            <setting name="AppWidth" serializeAs="String">
+                <value>400</value>
+            </setting>
+            <setting name="AppHeight" serializeAs="String">
+                <value>600</value>
+            </setting>
+            <setting name="ThemName" serializeAs="String">
+                <value>Default</value>
+            </setting>
+        </RevitAddinManager.Properties.App>
+    </userSettings>
+</configuration>
\ No newline at end of file
diff --git a/AddInManager/Model/SettingBindingExtension.cs b/AddInManager/Model/SettingBindingExtension.cs
new file mode 100644
index 0000000..22f0447
--- /dev/null
+++ b/AddInManager/Model/SettingBindingExtension.cs
@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Data;
+
+namespace RevitAddinManager.Model
+{
+    /// <summary>
+    /// source : https://thomaslevesque.com/2008/11/18/wpf-binding-to-application-settings-using-a-markup-extension/
+    /// </summary>
+    public class SettingBindingExtension : Binding
+    {
+        public SettingBindingExtension()
+        {
+            Initialize();
+        }
+
+        public SettingBindingExtension(string path)
+            : base(path)
+        {
+            Initialize();
+        }
+
+        private void Initialize()
+        {
+            this.Source = Properties.App.Default;
+            this.Mode = BindingMode.OneTime;
+        }
+    }
+}
diff --git a/AddInManager/Properties/App.Designer.cs b/AddInManager/Properties/App.Designer.cs
new file mode 100644
index 0000000..07dee16
--- /dev/null
+++ b/AddInManager/Properties/App.Designer.cs
@@ -0,0 +1,62 @@
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace RevitAddinManager.Properties {
+    
+    
+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "17.4.0.0")]
+    internal sealed partial class App : global::System.Configuration.ApplicationSettingsBase {
+        
+        private static App defaultInstance = ((App)(global::System.Configuration.ApplicationSettingsBase.Synchronized(new App())));
+        
+        public static App Default {
+            get {
+                return defaultInstance;
+            }
+        }
+        
+        [global::System.Configuration.UserScopedSettingAttribute()]
+        [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+        [global::System.Configuration.DefaultSettingValueAttribute("400")]
+        public double AppWidth {
+            get {
+                return ((double)(this["AppWidth"]));
+            }
+            set {
+                this["AppWidth"] = value;
+            }
+        }
+        
+        [global::System.Configuration.UserScopedSettingAttribute()]
+        [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+        [global::System.Configuration.DefaultSettingValueAttribute("600")]
+        public double AppHeight {
+            get {
+                return ((double)(this["AppHeight"]));
+            }
+            set {
+                this["AppHeight"] = value;
+            }
+        }
+        
+        [global::System.Configuration.UserScopedSettingAttribute()]
+        [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+        [global::System.Configuration.DefaultSettingValueAttribute("Default")]
+        public string ThemName {
+            get {
+                return ((string)(this["ThemName"]));
+            }
+            set {
+                this["ThemName"] = value;
+            }
+        }
+    }
+}
diff --git a/AddInManager/Properties/App.settings b/AddInManager/Properties/App.settings
new file mode 100644
index 0000000..3e8293f
--- /dev/null
+++ b/AddInManager/Properties/App.settings
@@ -0,0 +1,15 @@
+<?xml version='1.0' encoding='utf-8'?>
+<SettingsFile xmlns="http://schemas.microsoft.com/VisualStudio/2004/01/settings" CurrentProfile="(Default)" GeneratedClassNamespace="RevitAddinManager.Properties" GeneratedClassName="App">
+  <Profiles />
+  <Settings>
+    <Setting Name="AppWidth" Type="System.Double" Scope="User">
+      <Value Profile="(Default)">400</Value>
+    </Setting>
+    <Setting Name="AppHeight" Type="System.Double" Scope="User">
+      <Value Profile="(Default)">600</Value>
+    </Setting>
+    <Setting Name="ThemName" Type="System.String" Scope="User">
+      <Value Profile="(Default)">Default</Value>
+    </Setting>
+  </Settings>
+</SettingsFile>
\ No newline at end of file
diff --git a/AddInManager/Properties/Settings.Designer.cs b/AddInManager/Properties/Settings.Designer.cs
deleted file mode 100644
index 4e43697..0000000
--- a/AddInManager/Properties/Settings.Designer.cs
+++ /dev/null
@@ -1,26 +0,0 @@
-//------------------------------------------------------------------------------
-// <auto-generated>
-//     This code was generated by a tool.
-//     Runtime Version:4.0.30319.42000
-//
-//     Changes to this file may cause incorrect behavior and will be lost if
-//     the code is regenerated.
-// </auto-generated>
-//------------------------------------------------------------------------------
-
-namespace RevitAddinManager.Properties {
-    
-    
-    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
-    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "17.1.0.0")]
-    internal sealed partial class Settings : global::System.Configuration.ApplicationSettingsBase {
-        
-        private static Settings defaultInstance = ((Settings)(global::System.Configuration.ApplicationSettingsBase.Synchronized(new Settings())));
-        
-        public static Settings Default {
-            get {
-                return defaultInstance;
-            }
-        }
-    }
-}
diff --git a/AddInManager/Properties/Settings.settings b/AddInManager/Properties/Settings.settings
deleted file mode 100644
index 049245f..0000000
--- a/AddInManager/Properties/Settings.settings
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version='1.0' encoding='utf-8'?>
-<SettingsFile xmlns="http://schemas.microsoft.com/VisualStudio/2004/01/settings" CurrentProfile="(Default)">
-  <Profiles>
-    <Profile Name="(Default)" />
-  </Profiles>
-</SettingsFile>
diff --git a/AddInManager/RevitAddinManager.csproj b/AddInManager/RevitAddinManager.csproj
index 02585f9..7c88010 100644
--- a/AddInManager/RevitAddinManager.csproj
+++ b/AddInManager/RevitAddinManager.csproj
@@ -84,10 +84,10 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Compile Update="Properties\Settings.Designer.cs">
+    <Compile Update="Properties\App.Designer.cs">
       <DesignTimeSharedInput>True</DesignTimeSharedInput>
       <AutoGen>True</AutoGen>
-      <DependentUpon>Settings.settings</DependentUpon>
+      <DependentUpon>App.settings</DependentUpon>
     </Compile>
     <Compile Update="Resource.Designer.cs">
       <DesignTime>True</DesignTime>
@@ -104,9 +104,9 @@
   </ItemGroup>
 
   <ItemGroup>
-    <None Update="Properties\Settings.settings">
+    <None Update="Properties\App.settings">
       <Generator>SettingsSingleFileGenerator</Generator>
-      <LastGenOutput>Settings.Designer.cs</LastGenOutput>
+      <LastGenOutput>App.Designer.cs</LastGenOutput>
     </None>
     <None Update="View\AssemblyLoader.xaml">
       <Generator>MSBuild:Compile</Generator>
diff --git a/AddInManager/Themes/Styles/Default.xaml b/AddInManager/Themes/Styles/Default.xaml
index 51dfc83..6aad9c5 100644
--- a/AddInManager/Themes/Styles/Default.xaml
+++ b/AddInManager/Themes/Styles/Default.xaml
@@ -1,10 +1,10 @@
-<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:control="clr-namespace:RevitAddinManager.View.Control"
-                    xmlns:converters="clr-namespace:RevitAddinManager.Themes.Converters">
+<ResourceDictionary
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:control="clr-namespace:RevitAddinManager.View.Control"
+    xmlns:converters="clr-namespace:RevitAddinManager.Themes.Converters">
     <ResourceDictionary.MergedDictionaries>
-        <ResourceDictionary
-            Source="/PresentationFramework.Royale;V3.0.0.0;31bf3856ad364e35;component\themes\royale.normalcolor.xaml" />
+        <ResourceDictionary Source="/PresentationFramework.Royale;V3.0.0.0;31bf3856ad364e35;component\themes\royale.normalcolor.xaml" />
         <!-- <ResourceDictionary Source="/RevitAddinManager;component\Themes\Styles/DarkTheme.xaml" /> -->
         <!-- <ResourceDictionary Source="/RevitAddinManager;component\Themes\Styles/LightTheme.xaml" /> -->
     </ResourceDictionary.MergedDictionaries>
@@ -14,23 +14,38 @@
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="ToggleButton">
-                    <Grid Width="15" Height="13" SnapsToDevicePixels="True">
-                        <Rectangle Width="9" Height="9" Stroke="#919191" SnapsToDevicePixels="true">
+                    <Grid
+                        Width="15"
+                        Height="13"
+                        SnapsToDevicePixels="True">
+                        <Rectangle
+                            Width="9"
+                            Height="9"
+                            SnapsToDevicePixels="true"
+                            Stroke="#919191">
                             <Rectangle.Fill>
-                                <LinearGradientBrush EndPoint="0.5,2" StartPoint="0.5,0">
-                                    <GradientStop Color="White" Offset="0" />
-                                    <GradientStop Color="Silver" Offset="0.5" />
-                                    <GradientStop Color="LightGray" Offset="1" />
+                                <LinearGradientBrush StartPoint="0.5,0" EndPoint="0.5,2">
+                                    <GradientStop Offset="0" Color="White" />
+                                    <GradientStop Offset="0.5" Color="Silver" />
+                                    <GradientStop Offset="1" Color="LightGray" />
                                 </LinearGradientBrush>
                             </Rectangle.Fill>
                         </Rectangle>
-                        <Rectangle x:Name="ExpandPath" Width="1" Height="5" Stroke="Black"
-                                   SnapsToDevicePixels="true" />
-                        <Rectangle Width="5" Height="1" Stroke="Black" SnapsToDevicePixels="true" />
+                        <Rectangle
+                            x:Name="ExpandPath"
+                            Width="1"
+                            Height="5"
+                            SnapsToDevicePixels="true"
+                            Stroke="Black" />
+                        <Rectangle
+                            Width="5"
+                            Height="1"
+                            SnapsToDevicePixels="true"
+                            Stroke="Black" />
                     </Grid>
                     <ControlTemplate.Triggers>
                         <Trigger Property="IsChecked" Value="True">
-                            <Setter Property="Visibility" TargetName="ExpandPath" Value="Collapsed" />
+                            <Setter TargetName="ExpandPath" Property="Visibility" Value="Collapsed" />
                         </Trigger>
                     </ControlTemplate.Triggers>
                 </ControlTemplate>
@@ -48,7 +63,7 @@
                 <ControlTemplate TargetType="{x:Type TreeViewItem}">
                     <Grid>
                         <Grid.ColumnDefinitions>
-                            <ColumnDefinition MinWidth="19" Width="Auto" />
+                            <ColumnDefinition Width="Auto" MinWidth="19" />
                             <ColumnDefinition Width="Auto" />
                             <ColumnDefinition Width="*" />
                         </Grid.ColumnDefinitions>
@@ -57,39 +72,56 @@
                             <RowDefinition />
                         </Grid.RowDefinitions>
 
-                        <!-- Connecting Lines -->
-                        <Rectangle x:Name="HorLn" Margin="9,1,0,0" Height="1" Stroke="#DCDCDC"
-                                   SnapsToDevicePixels="True" />
-                        <Rectangle x:Name="VerLn" Width="1" Stroke="#DCDCDC" Margin="0,0,1,0"
-                                   Grid.RowSpan="2" SnapsToDevicePixels="true" Fill="White" />
-                        <ToggleButton Margin="-1,0,0,0" x:Name="Expander"
-                                      Style="{StaticResource ExpandCollapseToggleStyle}"
-                                      IsChecked="{Binding Path=IsExpanded, RelativeSource={RelativeSource TemplatedParent}}"
-                                      ClickMode="Press" />
-                        <Border Name="Bd" Grid.Column="1"
-                                Background="{TemplateBinding Background}"
-                                BorderBrush="{TemplateBinding BorderBrush}"
-                                BorderThickness="{TemplateBinding BorderThickness}"
-                                Padding="{TemplateBinding Padding}" SnapsToDevicePixels="True">
-                            <ContentPresenter x:Name="PART_Header" ContentSource="Header"
-                                              HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
-                                              MinWidth="20" />
+                        <!--  Connecting Lines  -->
+                        <Rectangle
+                            x:Name="HorLn"
+                            Height="1"
+                            Margin="9,1,0,0"
+                            SnapsToDevicePixels="True"
+                            Stroke="#DCDCDC" />
+                        <Rectangle
+                            x:Name="VerLn"
+                            Grid.RowSpan="2"
+                            Width="1"
+                            Margin="0,0,1,0"
+                            Fill="White"
+                            SnapsToDevicePixels="true"
+                            Stroke="#DCDCDC" />
+                        <ToggleButton
+                            x:Name="Expander"
+                            Margin="-1,0,0,0"
+                            ClickMode="Press"
+                            IsChecked="{Binding Path=IsExpanded, RelativeSource={RelativeSource TemplatedParent}}"
+                            Style="{StaticResource ExpandCollapseToggleStyle}" />
+                        <Border
+                            Name="Bd"
+                            Grid.Column="1"
+                            Padding="{TemplateBinding Padding}"
+                            Background="{TemplateBinding Background}"
+                            BorderBrush="{TemplateBinding BorderBrush}"
+                            BorderThickness="{TemplateBinding BorderThickness}"
+                            SnapsToDevicePixels="True">
+                            <ContentPresenter
+                                x:Name="PART_Header"
+                                MinWidth="20"
+                                HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                ContentSource="Header" />
                         </Border>
-                        <ItemsPresenter x:Name="ItemsHost" Grid.Row="1" Grid.Column="1"
-                                        Grid.ColumnSpan="2" />
+                        <ItemsPresenter
+                            x:Name="ItemsHost"
+                            Grid.Row="1"
+                            Grid.Column="1"
+                            Grid.ColumnSpan="2" />
                     </Grid>
                     <ControlTemplate.Triggers>
 
-                        <!-- This trigger changes the connecting lines if the item is the last in the list -->
-                        <DataTrigger
-                            Binding="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource LineConverter}}"
-                            Value="true">
+                        <!--  This trigger changes the connecting lines if the item is the last in the list  -->
+                        <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource LineConverter}}" Value="true">
                             <Setter TargetName="VerLn" Property="Height" Value="9" />
                             <Setter TargetName="VerLn" Property="VerticalAlignment" Value="Top" />
                         </DataTrigger>
                         <Trigger Property="IsExpanded" Value="false">
-                            <Setter TargetName="ItemsHost" Property="Visibility"
-                                    Value="Collapsed" />
+                            <Setter TargetName="ItemsHost" Property="Visibility" Value="Collapsed" />
                         </Trigger>
                         <Trigger Property="HasItems" Value="false">
                             <Setter TargetName="Expander" Property="Visibility" Value="Hidden" />
@@ -109,10 +141,8 @@
                             <Setter TargetName="PART_Header" Property="MinHeight" Value="19" />
                         </MultiTrigger>
                         <Trigger Property="IsSelected" Value="true">
-                            <Setter TargetName="Bd" Property="Background"
-                                    Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
-                            <Setter Property="Foreground"
-                                    Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}" />
+                            <Setter TargetName="Bd" Property="Background" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
+                            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}" />
                         </Trigger>
                         <!-- <MultiTrigger> -->
                         <!--     <MultiTrigger.Conditions> -->
@@ -123,8 +153,7 @@
                         <!--     <Setter Property="Foreground" Value="White" /> -->
                         <!-- </MultiTrigger> -->
                         <Trigger Property="IsEnabled" Value="false">
-                            <Setter Property="Foreground"
-                                    Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
+                            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
                         </Trigger>
                     </ControlTemplate.Triggers>
                 </ControlTemplate>
@@ -137,11 +166,9 @@
             <MultiTrigger>
                 <MultiTrigger.Conditions>
                     <Condition Property="IsSelected" Value="true" />
-                    <Condition Property="control:ExtendedTreeView.ContextMenuOpened"
-                               Value="true" />
+                    <Condition Property="control:ExtendedTreeView.ContextMenuOpened" Value="true" />
                 </MultiTrigger.Conditions>
-                <Setter Property="Background"
-                        Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
+                <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
                 <Setter Property="Foreground" Value="Red" />
             </MultiTrigger>
         </Style.Triggers>
diff --git a/AddInManager/View/FrmAddInManager.xaml b/AddInManager/View/FrmAddInManager.xaml
index 576aeaa..217d4a7 100644
--- a/AddInManager/View/FrmAddInManager.xaml
+++ b/AddInManager/View/FrmAddInManager.xaml
@@ -9,14 +9,15 @@
     xmlns:model="clr-namespace:RevitAddinManager.Model"
     xmlns:viewModel="clr-namespace:RevitAddinManager.ViewModel"
     Title="Revit Add In Manager"
-    Width="400"
-    Height="600"
+    Width="{model:SettingBinding AppWidth}"
+    Height="{model:SettingBinding AppHeight}"
     MinWidth="400"
     MinHeight="400"
     d:DataContext="{d:DesignInstance viewModel:AddInManagerViewModel}"
     FocusManager.FocusedElement="{Binding ElementName=tbxSearch}"
     Icon="../Resources/dev.ico"
     PreviewKeyDown="CloseFormEvent"
+    SizeChanged="FrmSizeChanged"
     mc:Ignorable="d">
     <Window.Resources>
         <ResourceDictionary>
@@ -102,7 +103,7 @@
         </Grid>
 
         <Grid Grid.Row="1">
-            <TabControl x:Name="TabControl"   SelectedIndex="{Binding SelectedTab, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
+            <TabControl x:Name="TabControl" SelectedIndex="{Binding SelectedTab, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
                 <TabItem
                     x:Name="TabCommand"
                     FontSize="14"
diff --git a/AddInManager/View/FrmAddInManager.xaml.cs b/AddInManager/View/FrmAddInManager.xaml.cs
index 5f1665f..c21837f 100644
--- a/AddInManager/View/FrmAddInManager.xaml.cs
+++ b/AddInManager/View/FrmAddInManager.xaml.cs
@@ -2,6 +2,7 @@
 using System.Windows;
 using System.Windows.Input;
 using RevitAddinManager.Model;
+using System.Windows.Threading;
 
 namespace RevitAddinManager.View;
 
@@ -17,6 +18,8 @@ public FrmAddInManager(AddInManagerViewModel vm)
         InitializeComponent();
         DataContext = vm;
         viewModel = vm;
+        this.Width = Properties.App.Default.AppWidth;
+        this.Height = Properties.App.Default.AppHeight;
         App.FrmAddInManager = this;
         ThemManager.ChangeThem(true);
         Title += DefaultSetting.Version;
@@ -132,5 +135,29 @@ private void CloseFormEvent(object sender, KeyEventArgs e)
     {
         if (e.Key == Key.Escape) Close();
     }
+    private DispatcherTimer SizeChangedDebouncer;
+    private void FrmSizeChanged(object sender, SizeChangedEventArgs e)
+    {
+        SizeChangedDebouncer = Debounce(SizeChangedDebouncer, TimeSpan.FromSeconds(1), SaveUserSettings);
+    }
+
+    private void SaveUserSettings()
+    {
+        Properties.App.Default.AppHeight = Height;
+        Properties.App.Default.AppWidth = Width;
+        Properties.App.Default.Save();
+    }
+    private  DispatcherTimer Debounce(DispatcherTimer dispatcher, TimeSpan interval, Action action)
+    {
+        dispatcher?.Stop();
+        dispatcher = null;
+        dispatcher = new DispatcherTimer(interval, DispatcherPriority.ApplicationIdle, (s, e) =>
+        {
+            dispatcher?.Stop();
+            action.Invoke();
+        }, Dispatcher.CurrentDispatcher);
+        dispatcher?.Start();
 
+        return dispatcher;
+    }
 }
\ No newline at end of file