diff --git a/js/app.js b/js/app.js
index 3f9f515d1d..3aab5fd8dc 100644
--- a/js/app.js
+++ b/js/app.js
@@ -152,7 +152,6 @@ $(document).ready(function () {
 
     initPlugins();
 
-    var x = 0;
     $('a[data-ui-loader], button[data-ui-loader]').on('click', function () {
         var $this = $(this);
         
@@ -160,17 +159,19 @@ $(document).ready(function () {
             return false;
         }
         
+        //Adopt current color for the loader animation
         var color = $this.css('color') || '#ffffff';
         var $loader = $('<span class="loader"><span class="sk-spinner sk-spinner-three-bounce"><span class="sk-bounce1"></span><span class="sk-bounce2"></span><span class="sk-bounce3"></span></span></span>');
         
+        //Align bouncer animation color and size
         $loader.find('.sk-bounce1, .sk-bounce2, .sk-bounce3')
                 .addClass('disabled')
                 .css( {'background-color': color, 'width': '10px', 'height': '10px'});
         
+        //The loader does have some margin we have to hide
         $this.css('overflow', 'hidden');
         $this.addClass('disabled');
         
-        
         //Prevent the container from resizing
         $this.css('min-width', this.getBoundingClientRect().width);
         $this.data('text', $this.text());
@@ -182,7 +183,7 @@ $(document).ready(function () {
             $('[data-ui-loader]').each(function() {
                 var $this = $(this);
                 if($this.find('.loader').length) {
-                    $this.html($(this).data('text'));
+                    $this.html($this.data('text'));
                     $this.removeClass('disabled');
                 }
             });
diff --git a/protected/humhub/compat/HForm.php b/protected/humhub/compat/HForm.php
index 56e6c4eec0..7c510c05ac 100644
--- a/protected/humhub/compat/HForm.php
+++ b/protected/humhub/compat/HForm.php
@@ -162,7 +162,7 @@ class HForm extends \yii\base\Component
         $output = "";
         foreach ($buttons as $buttonName => $definition) {
             if ($definition['type'] == 'submit') {
-                $output .= \yii\helpers\Html::submitButton($definition['label'], ['name' => $buttonName, 'class' => $definition['class']]);
+                $output .= \yii\helpers\Html::submitButton($definition['label'], ['name' => $buttonName, 'class' => $definition['class'], 'data-ui-loader' => '']);
                 $output .= "&nbsp;";
             }
         }
diff --git a/protected/humhub/modules/space/models/Space.php b/protected/humhub/modules/space/models/Space.php
index 415b617f6d..71193f4a34 100644
--- a/protected/humhub/modules/space/models/Space.php
+++ b/protected/humhub/modules/space/models/Space.php
@@ -80,7 +80,7 @@ class Space extends ContentContainerActiveRecord implements \humhub\modules\sear
     {
         $rules = [
             [['join_policy', 'visibility', 'status', 'created_by', 'updated_by', 'auto_add_new_members', 'default_content_visibility'], 'integer'],
-            
+            [['indexUrl'], 'string'],
             [['name'], 'required'],
             [['description', 'tags', 'color'], 'string'],
             [['created_at', 'updated_at'], 'safe'],
@@ -103,7 +103,7 @@ class Space extends ContentContainerActiveRecord implements \humhub\modules\sear
     {
         $scenarios = parent::scenarios();
 
-        $scenarios['edit'] = ['name', 'color', 'description', 'tags','indexUrl', 'join_policy', 'visibility', 'default_content_visibility'];
+        $scenarios['edit'] = ['name', 'color', 'description', 'tags', 'indexUrl', 'join_policy', 'visibility', 'default_content_visibility'];
         $scenarios['create'] = ['name', 'color', 'description', 'join_policy', 'visibility'];
 
         return $scenarios;
diff --git a/protected/humhub/modules/space/modules/manage/views/default/index.php b/protected/humhub/modules/space/modules/manage/views/default/index.php
index 2b81bce066..f762cdcf38 100644
--- a/protected/humhub/modules/space/modules/manage/views/default/index.php
+++ b/protected/humhub/modules/space/modules/manage/views/default/index.php
@@ -43,7 +43,7 @@ $this->registerCssFile('@web/resources/space/colorpicker/css/bootstrap-colorpick
         </div>
         
 
-        <?php echo Html::submitButton(Yii::t('SpaceModule.views_admin_edit', 'Save'), array('class' => 'btn btn-primary')); ?>
+        <?php echo Html::submitButton(Yii::t('SpaceModule.views_admin_edit', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
         <?php echo \humhub\widgets\DataSaved::widget(); ?>
 
diff --git a/protected/humhub/modules/space/modules/manage/views/default/security.php b/protected/humhub/modules/space/modules/manage/views/default/security.php
index 7fe5d8bcca..1ec0a527ff 100644
--- a/protected/humhub/modules/space/modules/manage/views/default/security.php
+++ b/protected/humhub/modules/space/modules/manage/views/default/security.php
@@ -37,7 +37,7 @@ use humhub\modules\space\modules\manage\widgets\DefaultMenu;
         <?php echo $form->field($model, 'default_content_visibility')->dropdownList($contentVisibilities); ?>
         <p class="help-block"><?php echo Yii::t('SpaceModule.views_admin_edit', 'Choose if new content should be public or private by default'); ?></p>
 
-        <?php echo Html::submitButton(Yii::t('base', 'Save'), array('class' => 'btn btn-primary')); ?>
+        <?php echo Html::submitButton(Yii::t('base', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
         <?php echo \humhub\widgets\DataSaved::widget(); ?>
 
diff --git a/protected/humhub/modules/user/Events.php b/protected/humhub/modules/user/Events.php
index c987d8b038..bfe7f1b1d7 100644
--- a/protected/humhub/modules/user/Events.php
+++ b/protected/humhub/modules/user/Events.php
@@ -6,6 +6,7 @@ use Yii;
 use humhub\modules\user\models\User;
 use humhub\modules\user\models\Password;
 use humhub\modules\user\models\Profile;
+use humhub\modules\user\models\GroupUser;
 use humhub\modules\user\models\Mentioning;
 use humhub\modules\user\models\Follow;
 
@@ -50,13 +51,10 @@ class Events extends \yii\base\Object
         $integrityController = $event->sender;
 
         $integrityController->showTestHeadline("User Module - Users (" . User::find()->count() . " entries)");
-        foreach (User::find()->joinWith(['profile', 'group'])->all() as $user) {
+        foreach (User::find()->joinWith(['profile'])->all() as $user) {
             if ($user->profile == null) {
                 $integrityController->showWarning("User with id " . $user->id . " has no profile record!");
             }
-            if (!$user->hasGroup()) {
-                $integrityController->showWarning("User with id " . $user->id . " has no group assignment!");
-            }
         }
         
         foreach (GroupUser::find()->joinWith(['user'])->all() as $groupUser) {
diff --git a/protected/humhub/modules/user/views/account/changeEmail.php b/protected/humhub/modules/user/views/account/changeEmail.php
index b2775f6e70..544c026549 100644
--- a/protected/humhub/modules/user/views/account/changeEmail.php
+++ b/protected/humhub/modules/user/views/account/changeEmail.php
@@ -22,7 +22,7 @@ use \humhub\compat\CHtml;
     <?php echo $form->field($model, 'newEmail')->textInput(['maxlength' => 45]); ?>
 
     <hr>
-    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_changeEmail', 'Save'), array('class' => 'btn btn-primary')); ?>
+    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_changeEmail', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
     <!-- show flash message after saving -->
     <?php echo \humhub\widgets\DataSaved::widget(); ?>
diff --git a/protected/humhub/modules/user/views/account/changePassword.php b/protected/humhub/modules/user/views/account/changePassword.php
index 736f6f8d83..5e6f7c2ef5 100644
--- a/protected/humhub/modules/user/views/account/changePassword.php
+++ b/protected/humhub/modules/user/views/account/changePassword.php
@@ -18,7 +18,7 @@ use humhub\compat\CHtml;
     <?php echo $form->field($model, 'newPasswordConfirm')->passwordInput(['maxlength' => 45]); ?>
 
     <hr>
-    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_changePassword', 'Save'), array('class' => 'btn btn-primary')); ?>
+    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_changePassword', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
 
     <!-- show flash message after saving -->
diff --git a/protected/humhub/modules/user/views/account/editSettings.php b/protected/humhub/modules/user/views/account/editSettings.php
index 355d8696a6..eda39f4340 100644
--- a/protected/humhub/modules/user/views/account/editSettings.php
+++ b/protected/humhub/modules/user/views/account/editSettings.php
@@ -43,7 +43,7 @@ use \humhub\models\Setting;
     <?php endif; ?>
     <hr>
 
-    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_editSettings', 'Save'), array('class' => 'btn btn-primary')); ?>
+    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_editSettings', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
     <!-- show flash message after saving -->
     <?php echo \humhub\widgets\DataSaved::widget(); ?>
diff --git a/protected/humhub/modules/user/views/account/emailing.php b/protected/humhub/modules/user/views/account/emailing.php
index 96ebcd0f88..52a635e0d5 100644
--- a/protected/humhub/modules/user/views/account/emailing.php
+++ b/protected/humhub/modules/user/views/account/emailing.php
@@ -46,7 +46,7 @@ use humhub\modules\user\models\User;
 
     <hr>
 
-    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_emailing', 'Save'), array('class' => 'btn btn-primary')); ?>
+    <?php echo CHtml::submitButton(Yii::t('UserModule.views_account_emailing', 'Save'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
 
     <!-- show flash message after saving -->
     <?php echo \humhub\widgets\DataSaved::widget(); ?>