diff --git a/MultiTerm.Core.Tests/MultiTerm.Protocols.Tests.csproj b/MultiTerm.Core.Tests/MultiTerm.Protocols.Tests.csproj
index 413d002..e80d71e 100644
--- a/MultiTerm.Core.Tests/MultiTerm.Protocols.Tests.csproj
+++ b/MultiTerm.Core.Tests/MultiTerm.Protocols.Tests.csproj
@@ -14,7 +14,6 @@
     <PackageReference Include="NUnit" Version="3.13.3" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.3.0" />
     <PackageReference Include="NUnit.Analyzers" Version="3.5.0" />
-    <PackageReference Include="coverlet.collector" Version="3.1.2" />
   </ItemGroup>
 
 	<ItemGroup>
diff --git a/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.cs b/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.cs
index a799c9a..7f658de 100644
--- a/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.cs
+++ b/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.cs
@@ -5,6 +5,7 @@ using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.ComponentModel;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Documents;
@@ -80,15 +81,6 @@ public class MultiFormatTextBox : Control
             typeof(MultiFormatTextBox));
     }
 
-    ~MultiFormatTextBox()
-    {
-        // unregister events
-        if (this.CurrentMultiFormatString != null && this.CurrentMultiFormatString is INotifyCollectionChanged incc)
-        {
-            incc.CollectionChanged -= this.MultiFormatString_CollectionChanged;
-        }
-    }
-
     public override void OnApplyTemplate()
     {
         base.OnApplyTemplate();
@@ -145,6 +137,10 @@ public class MultiFormatTextBox : Control
                 incc.CollectionChanged += mftb.MultiFormatString_CollectionChanged;
             }
         }
+        else if(mftb.CurrentMultiFormatString == null)
+        {
+            mftb.ResetTextBox();
+        }
     }
 
     /// <summary>
@@ -170,8 +166,7 @@ public class MultiFormatTextBox : Control
 
             case NotifyCollectionChangedAction.Reset:
                 // clear richtextbox add new paragraph
-                this.richTextBox!.Document.Blocks.Clear();
-                this.richTextBox!.Document.Blocks.Add(new Paragraph());
+                this.ResetTextBox();
                 break;
 
             case NotifyCollectionChangedAction.Replace:
@@ -270,6 +265,15 @@ public class MultiFormatTextBox : Control
         this.SetRtbCaretPosition(indexCounter);
     }
 
+    /// <summary>
+    /// Clear richtextbox adds new paragraph.
+    /// </summary>
+    private void ResetTextBox()
+    {
+        this.richTextBox!.Document.Blocks.Clear();
+        this.richTextBox!.Document.Blocks.Add(new Paragraph());
+    }
+
     private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
     {
         lock (lockObj) // lock so no richtextbox textchanged event can happen
diff --git a/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.xaml b/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.xaml
index 9477f95..7d81f39 100644
--- a/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.xaml
+++ b/MultiTerm.Wpf.CustomControl/MultiFormatTextBox/MultiFormatTextBox.xaml
@@ -21,7 +21,7 @@
                     <DockPanel LastChildFill="True">
                         <ComboBox DockPanel.Dock="Left" x:Name="PART_ComboBox" Width="70"></ComboBox>
                         <RichTextBox DockPanel.Dock="Right" VerticalContentAlignment="Center" x:Name="PART_RichTextBox" 
-                                     Style="{StaticResource TextFontStyle}"></RichTextBox>
+                                     Style="{StaticResource TextFontStyle}" Padding="0 5"></RichTextBox>
                     </DockPanel>
                 </ControlTemplate>
             </Setter.Value>
diff --git a/MultiTerm.Wpf/ValueConverters/ProtocolTypeToIconConverter.cs b/MultiTerm.Wpf/ValueConverters/ProtocolTypeToIconConverter.cs
index a9447a6..5c1d249 100644
--- a/MultiTerm.Wpf/ValueConverters/ProtocolTypeToIconConverter.cs
+++ b/MultiTerm.Wpf/ValueConverters/ProtocolTypeToIconConverter.cs
@@ -17,9 +17,7 @@ internal class ProtocolTypeToIconConverter : IValueConverter
         { throw new ArgumentException($"Wrong object provided, can only convert from type {nameof(ProtocolType)}"); }
 
         string resourceFolderPath = "pack://application:,,,/Assets/";
-        //string path = $"{typeof(MainWindow).FullName};component/Assets/";
-        //string packUri = "pack://application:,,,/Assets/";
-
+        
         string fileName = protocolType switch
         {
             ProtocolType.Serial => "mdi-serial-port.png",