diff --git a/BeWoPlanerChat/bewoplaner-chat-android/app/build.gradle b/BeWoPlanerChat/bewoplaner-chat-android/app/build.gradle
index 5cee12a..9be1cb4 100644
--- a/BeWoPlanerChat/bewoplaner-chat-android/app/build.gradle
+++ b/BeWoPlanerChat/bewoplaner-chat-android/app/build.gradle
@@ -10,7 +10,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'io.fabric.tools:gradle:1.25.4'
+        classpath 'io.fabric.tools:gradle:1.28.0'
     }
 }
 
@@ -89,7 +89,7 @@ dependencies {
         exclude group: 'com.android.support'
     }
 
-    implementation('com.crashlytics.sdk.android:crashlytics:2.6.6@aar') {
+    implementation('com.crashlytics.sdk.android:crashlytics:2.10.1@aar') {
         transitive = true
     }
 
diff --git a/BeWoPlanerChat/bewoplaner-chat-android/build.gradle b/BeWoPlanerChat/bewoplaner-chat-android/build.gradle
index f70304d..0aab550 100644
--- a/BeWoPlanerChat/bewoplaner-chat-android/build.gradle
+++ b/BeWoPlanerChat/bewoplaner-chat-android/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.4.2'
+        classpath 'com.android.tools.build:gradle:4.0.1'
         classpath 'io.realm:realm-gradle-plugin:5.3.0'
 
         // NOTE: Do not place your application dependencies here; they belong
diff --git a/BeWoPlanerChat/bewoplaner-chat-android/gradle/wrapper/gradle-wrapper.properties b/BeWoPlanerChat/bewoplaner-chat-android/gradle/wrapper/gradle-wrapper.properties
index a0fbaad..c0d7638 100644
--- a/BeWoPlanerChat/bewoplaner-chat-android/gradle/wrapper/gradle-wrapper.properties
+++ b/BeWoPlanerChat/bewoplaner-chat-android/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Tue May 14 14:34:33 CEST 2019
+#Fri Aug 07 14:18:13 CEST 2020
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-all.zip
diff --git a/ChatController/ChatMainControl.xaml.cs b/ChatController/ChatMainControl.xaml.cs
index f4719ce..2b2d67b 100644
--- a/ChatController/ChatMainControl.xaml.cs
+++ b/ChatController/ChatMainControl.xaml.cs
@@ -24,6 +24,7 @@ using ChatController.HauptKlassen;
 using ChatController.LoginKlassen;
 using ChatController.Utilities;
 using ChatController.Utilities.Extensions;
+using Application = System.Windows.Forms.Application;
 using Button = System.Windows.Controls.Button;
 using Cursors = System.Windows.Input.Cursors;
 using DataFormats = System.Windows.DataFormats;
@@ -244,10 +245,11 @@ namespace ChatController
 
                 SelectContact(_ContactList.FirstOrDefault(f => f.GroupId.Equals(pGroupId)));
             };
-
+            
             notifyIcon.BalloonTipClosed += (sender, args) =>
             {
-                DisposeAndRemoveNotification((NotifyIcon)sender, pGroupId);
+                // TODO: wird beim ausblenden bzw. automatischem Schließen des "Balloons" ausgelöst
+                //DisposeAndRemoveNotification((NotifyIcon)sender, pGroupId);
             };
 
             _Group2NotifyIcons.AddOrUpdateValueInDictionary(pGroupId, notifyIcon);
@@ -261,7 +263,9 @@ namespace ChatController
             {
                 foreach(var notifyIcon in group2NotifyIcon.Value)
                 {
+                    notifyIcon.Icon = null;
                     notifyIcon.Dispose();
+                    Application.DoEvents();
                 }
             }
 
@@ -272,6 +276,9 @@ namespace ChatController
         {
             pNotification.Dispose();
             _Group2NotifyIcons.Remove(pGroupId);
+
+
+            Application.DoEvents();
         }
 
         public void ResetStyle()
diff --git a/PrototypChat/MainWindow.xaml.cs b/PrototypChat/MainWindow.xaml.cs
index 504010d..1d20e4a 100644
--- a/PrototypChat/MainWindow.xaml.cs
+++ b/PrototypChat/MainWindow.xaml.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Threading;
 using System.Windows;
 
 using ChatController.LoginKlassen;
@@ -43,6 +44,9 @@ namespace ownChat
             ChatMainControl.DeleteTempFiles();
             ChatMainControl.WriteToNewSyncFile();
             ChatMainControl.ClearNotifications();
+
+            Thread.Sleep(500);
+
             Environment.Exit(0);
         }
     }