Improve code quality

Flow.Launcher/MainWindow.xaml

@@ -20,13 +20,13 @@
     Closing="OnClosing"
     Deactivated="OnDeactivated"
     Icon="Images/app.png"
-    Initialized="OnInitialized"
     Left="{Binding Settings.WindowLeft, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
     Loaded="OnLoaded"
     LocationChanged="OnLocationChanged"
     Opacity="{Binding MainWindowOpacity, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"
     PreviewKeyDown="OnKeyDown"
     PreviewKeyUp="OnKeyUp"
+    PreviewMouseMove="OnPreviewMouseMove"
     ResizeMode="CanResize"
     ShowInTaskbar="False"
     SizeToContent="Height"
@@ -240,14 +240,14 @@
                             FontSize="{Binding QueryBoxFontSize, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                             InputMethod.PreferredImeConversionMode="{Binding StartWithEnglishMode, Converter={StaticResource BoolToIMEConversionModeConverter}}"
                             InputMethod.PreferredImeState="{Binding StartWithEnglishMode, Converter={StaticResource BoolToIMEStateConverter}}"
-                            PreviewDragOver="OnPreviewDragOver"
+                            PreviewDragOver="QueryTextBox_OnPreviewDragOver"
                             PreviewKeyUp="QueryTextBox_KeyUp"
                             Style="{DynamicResource QueryBoxStyle}"
                             Text="{Binding QueryText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                             Visibility="Visible"
                             WindowChrome.IsHitTestVisibleInChrome="True">
                             <TextBox.CommandBindings>
-                                <CommandBinding Command="ApplicationCommands.Copy" Executed="OnCopy" />
+                                <CommandBinding Command="ApplicationCommands.Copy" Executed="QueryTextBox_OnCopy" />
                             </TextBox.CommandBindings>
                             <TextBox.ContextMenu>
                                 <ContextMenu MinWidth="160">