diff --git a/protected/humhub/docs/CHANGELOG.md b/protected/humhub/docs/CHANGELOG.md
index 4ca13d6de5..3d7dec030d 100644
--- a/protected/humhub/docs/CHANGELOG.md
+++ b/protected/humhub/docs/CHANGELOG.md
@@ -3,6 +3,7 @@ HumHub Change Log
 1.2.1 (in developement)
 - Fix: Invite error in french language
 - Fix #2518: ActivityStreamWidget::EVENT_INIT is missed (githubjeka)
+- Enh: Fixed accessibility issues in Dashboard/Login/Profile
 
 1.2.0 (April 16, 2017)
 --------------------------------
diff --git a/protected/humhub/modules/comment/widgets/views/showComment.php b/protected/humhub/modules/comment/widgets/views/showComment.php
index 4823a237f8..fa976fa4f5 100644
--- a/protected/humhub/modules/comment/widgets/views/showComment.php
+++ b/protected/humhub/modules/comment/widgets/views/showComment.php
@@ -15,7 +15,9 @@ use humhub\modules\like\widgets\LikeLink;
         <div class="comment-entry-loader pull-right"></div>
         <ul class="nav nav-pills preferences">
             <li class="dropdown ">
-                <a class="dropdown-toggle" data-toggle="dropdown" href="#"><i class="fa fa-angle-down"></i></a>
+                <a class="dropdown-toggle" data-toggle="dropdown" href="#" aria-label="<?= Yii::t('base', 'Toggle comment menu'); ?>" aria-haspopup="true">
+                    <i class="fa fa-angle-down"></i>
+                </a>
 
                 <ul class="dropdown-menu pull-right">
                     <?php if ($canWrite): ?>
diff --git a/protected/humhub/modules/content/widgets/views/wallCreateContentForm.php b/protected/humhub/modules/content/widgets/views/wallCreateContentForm.php
index 746d2edf4e..e747106fa6 100644
--- a/protected/humhub/modules/content/widgets/views/wallCreateContentForm.php
+++ b/protected/humhub/modules/content/widgets/views/wallCreateContentForm.php
@@ -59,7 +59,7 @@ $this->registerJsConfig('content.form', [
                 <?= humhub\modules\file\widgets\FileHandlerButtonDropdown::widget(['primaryButton' => $uploadButton, 'handlers' => $fileHandlers, 'cssButtonClass' => 'btn-default']); ?>
 
                 <!-- public checkbox -->
-                <?php echo Html::checkbox("visibility", "", array('id' => 'contentForm_visibility', 'class' => 'contentForm hidden')); ?>
+                <?= Html::checkbox("visibility", "", ['id' => 'contentForm_visibility', 'class' => 'contentForm hidden', 'aria-hidden' => 'true', 'title' => Yii::t('ContentModule.widgets_views_contentForm', 'Content visibility') ]); ?>
 
                 <!-- content sharing -->
                 <div class="pull-right">
@@ -68,8 +68,8 @@ $this->registerJsConfig('content.form', [
 
                     <ul class="nav nav-pills preferences" style="right: 0; top: 5px;">
                         <li class="dropdown">
-                            <a class="dropdown-toggle" style="padding: 5px 10px;" data-toggle="dropdown" href="#"><i
-                                    class="fa fa-cogs"></i></a>
+                            <a class="dropdown-toggle" style="padding: 5px 10px;" data-toggle="dropdown" href="#" aria-label="<?= Yii::t('base', 'Toggle post menu'); ?>" aria-haspopup="true">
+                                <i class="fa fa-cogs"></i></a>
                             <ul class="dropdown-menu pull-right">
                                 <li>
                                     <a data-action-click="notifyUser">
@@ -79,7 +79,7 @@ $this->registerJsConfig('content.form', [
                                 <?php if ($canSwitchVisibility): ?>
                                     <li>
                                         <a id="contentForm_visibility_entry" data-action-click="changeVisibility">
-                                            <i class="fa fa-unlock"></i> <?php echo Yii::t('ContentModule.widgets_views_contentForm', 'Make public'); ?>
+                                            <i class="fa fa-unlock"></i> <?= Yii::t('ContentModule.widgets_views_contentForm', 'Make public'); ?>
                                         </a>
                                     </li>
                                 <?php endif; ?>
diff --git a/protected/humhub/modules/content/widgets/views/wallEntry.php b/protected/humhub/modules/content/widgets/views/wallEntry.php
index 5afacbb14a..4e9892dd2c 100644
--- a/protected/humhub/modules/content/widgets/views/wallEntry.php
+++ b/protected/humhub/modules/content/widgets/views/wallEntry.php
@@ -20,7 +20,9 @@ use humhub\modules\content\widgets\WallEntryLabels;
             <!-- start: show wall entry options -->
             <ul class="nav nav-pills preferences">
                 <li class="dropdown ">
-                    <a class="dropdown-toggle" data-toggle="dropdown" href="#"><i class="fa fa-angle-down"></i></a>
+                    <a class="dropdown-toggle" data-toggle="dropdown" href="#" aria-label="<?= Yii::t('base', 'Toggle stream entry menu'); ?>" aria-haspopup="true">
+                        <i class="fa fa-angle-down"></i>
+                    </a>
                     <ul class="dropdown-menu pull-right">
                         <?= WallEntryControls::widget(['object' => $object, 'wallEntryWidget' => $wallEntryWidget]); ?>
                     </ul>
diff --git a/protected/humhub/modules/file/converter/PreviewImage.php b/protected/humhub/modules/file/converter/PreviewImage.php
index bddceb681b..a5a05e9beb 100644
--- a/protected/humhub/modules/file/converter/PreviewImage.php
+++ b/protected/humhub/modules/file/converter/PreviewImage.php
@@ -44,9 +44,19 @@ class PreviewImage extends BaseConverter
         if ($file) {
             $this->applyFile($file);
         }
-
+        
         // Provide the natural height so the browser will include a placeholder height. Todo: smooth image loading
-        return \yii\helpers\Html::img($this->getUrl(), ['class' => 'animated fadeIn', 'height' => $this->height]);
+        return \yii\helpers\Html::img($this->getUrl(), ['class' => 'animated fadeIn', 'height' => $this->height, 'alt' => $this->getAltText()]);
+    }
+    
+    protected function getAltText($file = null)
+    {
+        if ($file) {
+            return Html::encode($file->file_name);
+        } else if($this->file) {
+            return Html::encode($this->file->file_name);
+        }
+        return '';
     }
 
     /**
diff --git a/protected/humhub/modules/file/widgets/UploadInput.php b/protected/humhub/modules/file/widgets/UploadInput.php
index 2a52d17c55..771119f1f7 100644
--- a/protected/humhub/modules/file/widgets/UploadInput.php
+++ b/protected/humhub/modules/file/widgets/UploadInput.php
@@ -130,7 +130,8 @@ class UploadInput extends \humhub\widgets\JsWidget
     public function getAttributes()
     {
         return [
-            'multiple' => 'multiple'
+            'multiple' => 'multiple',
+            'title' => Yii::t('base', 'Upload file')
         ];
     }
 
diff --git a/protected/humhub/modules/notification/widgets/views/overview.php b/protected/humhub/modules/notification/widgets/views/overview.php
index 87c7d6bf9b..2a5f7349e0 100755
--- a/protected/humhub/modules/notification/widgets/views/overview.php
+++ b/protected/humhub/modules/notification/widgets/views/overview.php
@@ -13,7 +13,7 @@ $this->registerJsConfig('notification', [
 
 ?>
 <div id="notification_widget" data-ui-widget="notification.NotificationDropDown" data-ui-init='<?= \yii\helpers\Json::encode($update); ?>' class="btn-group">
-    <a href="#" id="icon-notifications" data-action-click='toggle' data-toggle="dropdown" >
+    <a href="#" id="icon-notifications" data-action-click='toggle' aria-label="<?= Yii::t('NotificationModule.widgets_views_list', 'Open the notification dropdown menu')?>" data-toggle="dropdown" >
         <i class="fa fa-bell"></i>
     </a>
     
diff --git a/protected/humhub/modules/search/views/search/index.php b/protected/humhub/modules/search/views/search/index.php
index 337c4a20b7..d1beeff5a1 100644
--- a/protected/humhub/modules/search/views/search/index.php
+++ b/protected/humhub/modules/search/views/search/index.php
@@ -21,7 +21,8 @@ humhub\modules\stream\assets\StreamAsset::register($this);
                         <div class="col-md-6">
                             <?php $form = ActiveForm::begin(['action' => Url::to(['index']), 'method' => 'GET']); ?>
                                 <div class="form-group form-group-search">
-                                    <?= $form->field($model, 'keyword')->textInput(['placeholder' => Yii::t('SearchModule.views_search_index', 'Search for user, spaces and content'), 'class' => 'form-control form-search', 'id' => 'search-input-field'])->label(false); ?>
+                                    <?= $form->field($model, 'keyword')->textInput(['placeholder' => Yii::t('SearchModule.views_search_index', 'Search for user, spaces and content'), 
+                                        'title' => Yii::t('SearchModule.views_search_index', 'Search for user, spaces and content'), 'class' => 'form-control form-search', 'id' => 'search-input-field'])->label(false); ?>
                                     <?php echo Html::submitButton(Yii::t('base', 'Search'), ['class' => 'btn btn-default btn-sm form-button-search', 'data-ui-loader' => '']); ?>
                                 </div>
 
diff --git a/protected/humhub/modules/search/widgets/views/searchMenu.php b/protected/humhub/modules/search/widgets/views/searchMenu.php
index 7fb773a2ea..f746cddd2c 100644
--- a/protected/humhub/modules/search/widgets/views/searchMenu.php
+++ b/protected/humhub/modules/search/widgets/views/searchMenu.php
@@ -5,8 +5,9 @@ use yii\helpers\Url;
 ?>
 
 <li class="dropdown">
-    <a href="<?php echo Url::to(['/search/search/index']); ?>" id="search-menu" class="dropdown-toggle" >
-        <i class="fa fa-search"></i></a>
+    <a href="<?php echo Url::to(['/search/search/index']); ?>" id="search-menu" class="dropdown-toggle" aria-label="<?= Yii::t('SearchModule.views_search_index', 'Search for user, spaces and content') ?>">
+        <i class="fa fa-search"></i>
+    </a>
 </li>
 
 <script type="text/javascript">
diff --git a/protected/humhub/modules/space/widgets/views/spaceChooser.php b/protected/humhub/modules/space/widgets/views/spaceChooser.php
index 56adbf138b..9453e1de7e 100755
--- a/protected/humhub/modules/space/widgets/views/spaceChooser.php
+++ b/protected/humhub/modules/space/widgets/views/spaceChooser.php
@@ -46,7 +46,9 @@ $this->registerJsConfig('space.chooser', [
         <li>
             <form action="" class="dropdown-controls">
                 <div class="input-group">
-                    <input type="text" id="space-menu-search" class="form-control" autocomplete="off" placeholder="<?php echo Yii::t('SpaceModule.widgets_views_spaceChooser', 'Search'); ?>">
+                    <input type="text" id="space-menu-search" class="form-control" autocomplete="off" 
+                           placeholder="<?= Yii::t('SpaceModule.widgets_views_spaceChooser', 'Search'); ?>"
+                           title="<?= Yii::t('SpaceModule.widgets_views_spaceChooser', 'Search for spaces'); ?>">
                     <span id="space-directory-link" class="input-group-addon" >
                         <a href="<?= Url::to(['/directory/directory/spaces']); ?>">
                         <i class="fa fa-book"></i>
diff --git a/protected/humhub/modules/user/views/auth/login.php b/protected/humhub/modules/user/views/auth/login.php
index 4a446f7b34..e9282615c0 100644
--- a/protected/humhub/modules/user/views/auth/login.php
+++ b/protected/humhub/modules/user/views/auth/login.php
@@ -15,7 +15,7 @@ $this->pageTitle = Yii::t('UserModule.views_auth_login', 'Login');
     <div class="panel panel-default animated bounceIn" id="login-form"
          style="max-width: 300px; margin: 0 auto 20px; text-align: left;">
 
-        <div class="panel-heading"><?php echo Yii::t('UserModule.views_auth_login', '<strong>Please</strong> sign in'); ?></div>
+        <div class="panel-heading"><?= Yii::t('UserModule.views_auth_login', '<strong>Please</strong> sign in'); ?></div>
 
         <div class="panel-body">
 
@@ -29,26 +29,26 @@ $this->pageTitle = Yii::t('UserModule.views_auth_login', 'Login');
                 <?= AuthChoice::widget([]) ?>
             <?php else: ?>
                 <?php if ($canRegister) : ?>
-                    <p><?php echo Yii::t('UserModule.views_auth_login', "If you're already a member, please login with your username/email and password."); ?></p>
+                    <p><?= Yii::t('UserModule.views_auth_login', "If you're already a member, please login with your username/email and password."); ?></p>
                 <?php else: ?>
-                    <p><?php echo Yii::t('UserModule.views_auth_login', "Please login with your username/email and password."); ?></p>
+                    <p><?= Yii::t('UserModule.views_auth_login', "Please login with your username/email and password."); ?></p>
                 <?php endif; ?>
             <?php endif; ?>
 
             <?php $form = ActiveForm::begin(['id' => 'account-login-form', 'enableClientValidation' => false]); ?>
-            <?php echo $form->field($model, 'username')->textInput(['id' => 'login_username', 'placeholder' => $model->getAttributeLabel('username')])->label(false); ?>
-            <?php echo $form->field($model, 'password')->passwordInput(['id' => 'login_password', 'placeholder' => $model->getAttributeLabel('password')])->label(false); ?>
-            <?php echo $form->field($model, 'rememberMe')->checkbox(); ?>
+            <?= $form->field($model, 'username')->textInput(['id' => 'login_username', 'placeholder' => $model->getAttributeLabel('username'), 'aria-label' => $model->getAttributeLabel('username')])->label(false); ?>
+            <?= $form->field($model, 'password')->passwordInput(['id' => 'login_password', 'placeholder' => $model->getAttributeLabel('password'), 'aria-label' => $model->getAttributeLabel('password')])->label(false); ?>
+            <?= $form->field($model, 'rememberMe')->checkbox(); ?>
 
             <hr>
             <div class="row">
                 <div class="col-md-4">
-                    <?php echo CHtml::submitButton(Yii::t('UserModule.views_auth_login', 'Sign in'), array('id' => 'login-button', 'data-ui-loader' => "", 'class' => 'btn btn-large btn-primary')); ?>
+                    <?= CHtml::submitButton(Yii::t('UserModule.views_auth_login', 'Sign in'), array('id' => 'login-button', 'data-ui-loader' => "", 'class' => 'btn btn-large btn-primary')); ?>
                 </div>
                 <div class="col-md-8 text-right">
                     <small>
-                        <?php echo Yii::t('UserModule.views_auth_login', 'Forgot your password?'); ?>
-                        <a id="password-recovery-link" href="<?php echo Url::toRoute('/user/password-recovery'); ?>" data-pjax-prevent><br><?php echo Yii::t('UserModule.views_auth_login', 'Create a new one.') ?></a>
+                        <?= Yii::t('UserModule.views_auth_login', 'Forgot your password?'); ?>
+                        <a id="password-recovery-link" href="<?= Url::toRoute('/user/password-recovery'); ?>" data-pjax-prevent><br><?= Yii::t('UserModule.views_auth_login', 'Create a new one.') ?></a>
                     </small>
                 </div>
             </div>
@@ -65,16 +65,16 @@ $this->pageTitle = Yii::t('UserModule.views_auth_login', 'Login');
              class="panel panel-default animated bounceInLeft"
              style="max-width: 300px; margin: 0 auto 20px; text-align: left;">
 
-            <div class="panel-heading"><?php echo Yii::t('UserModule.views_auth_login', '<strong>Sign</strong> up') ?></div>
+            <div class="panel-heading"><?= Yii::t('UserModule.views_auth_login', '<strong>Sign</strong> up') ?></div>
 
             <div class="panel-body">
 
-                <p><?php echo Yii::t('UserModule.views_auth_login', "Don't have an account? Join the network by entering your e-mail address."); ?></p>
+                <p><?= Yii::t('UserModule.views_auth_login', "Don't have an account? Join the network by entering your e-mail address."); ?></p>
 
                 <?php $form = ActiveForm::begin(['id' => 'invite-form']); ?>
-                <?php echo $form->field($invite, 'email')->input('email', ['id' => 'register-email', 'placeholder' => $invite->getAttributeLabel('email')])->label(false); ?>
+                <?= $form->field($invite, 'email')->input('email', ['id' => 'register-email', 'placeholder' => $invite->getAttributeLabel('email'), 'aria-label' => $invite->getAttributeLabel('email')])->label(false); ?>
                 <hr>
-                <?php echo CHtml::submitButton(Yii::t('UserModule.views_auth_login', 'Register'), array('class' => 'btn btn-primary', 'data-ui-loader' => '')); ?>
+                <?= CHtml::submitButton(Yii::t('UserModule.views_auth_login', 'Register'), ['class' => 'btn btn-primary', 'data-ui-loader' => '']); ?>
 
                 <?php ActiveForm::end(); ?>
             </div>
diff --git a/protected/humhub/modules/user/widgets/Image.php b/protected/humhub/modules/user/widgets/Image.php
index ce3f260901..2592c993d8 100644
--- a/protected/humhub/modules/user/widgets/Image.php
+++ b/protected/humhub/modules/user/widgets/Image.php
@@ -8,6 +8,7 @@
 
 namespace humhub\modules\user\widgets;
 
+use Yii;
 use humhub\libs\Html;
 use humhub\components\Widget;
 
@@ -79,7 +80,7 @@ class Image extends Widget
     {
         Html::addCssClass($this->imageOptions, 'img-rounded');
         Html::addCssStyle($this->imageOptions, 'width: ' . $this->width . 'px; height: ' . $this->height . 'px');
-
+        
         if ($this->showTooltip) {
             $this->imageOptions['data-toggle'] = 'tooltip';
             $this->imageOptions['data-placement'] = 'top';
@@ -87,6 +88,7 @@ class Image extends Widget
             Html::addCssClass($this->imageOptions, 'tt');
         }
 
+        $this->imageOptions['alt'] = Yii::t('base', 'Profile picture of {displayName}', ['displayName' => Html::encode($this->user->displayName)]);
         $html = Html::img($this->user->getProfileImage()->getUrl(), $this->imageOptions);
 
         if ($this->link) {
diff --git a/protected/humhub/modules/user/widgets/views/profileHeader.php b/protected/humhub/modules/user/widgets/views/profileHeader.php
index e1c252baea..0a6f250bea 100644
--- a/protected/humhub/modules/user/widgets/views/profileHeader.php
+++ b/protected/humhub/modules/user/widgets/views/profileHeader.php
@@ -18,15 +18,15 @@ if ($allowModifyProfileBanner || $allowModifyProfileImage) {
 
         <div class="image-upload-container" style="width: 100%; height: 100%; overflow:hidden;">
             <!-- profile image output-->
-            <img class="img-profile-header-background" id="user-banner-image"
-                 src="<?php echo $user->getProfileBannerImage()->getUrl(); ?>"
+            <img class="img-profile-header-background" id="user-banner-image" alt="<?= Yii::t('base', 'Profile image of {displayName}', ['displayName' => Html::encode($user->displayName)]); ?>"
+                 src="<?= $user->getProfileBannerImage()->getUrl(); ?>"
                  width="100%" style="width: 100%; max-height: 192px;">
 
             <!-- check if the current user is the profile owner and can change the images -->
             <?php if ($allowModifyProfileBanner) : ?>
                 <form class="fileupload" id="bannerfileupload" action="" method="POST" enctype="multipart/form-data"
                       style="position: absolute; top: 0; left: 0; opacity: 0; width: 100%; height: 100%;">
-                    <input type="file" name="images[]">
+                    <input type="file" name="images[]" aria-hidden="true">
                 </form>
 
                 <?php
@@ -54,30 +54,28 @@ if ($allowModifyProfileBanner || $allowModifyProfileImage) {
 
             <!-- show user name and title -->
             <div class="img-profile-data">
-                <h1><?php echo Html::encode($user->displayName); ?></h1>
+                <h1><?= Html::encode($user->displayName); ?></h1>
 
-                <h2><?php echo Html::encode($user->profile->title); ?></h2>
+                <h2><?= Html::encode($user->profile->title); ?></h2>
             </div>
 
             <!-- check if the current user is the profile owner and can change the images -->
             <?php if ($allowModifyProfileBanner): ?>
                 <div class="image-upload-buttons" id="banner-image-upload-buttons">
-                    <a href="#" onclick="javascript:$('#bannerfileupload input').click();"
-                       class="btn btn-info btn-sm"><i
-                            class="fa fa-cloud-upload"></i></a>
+                    <a href="#" onclick="javascript:$('#bannerfileupload input').click();" class="btn btn-info btn-sm" aria-label="<?= Yii::t('UserModule.base', 'Upload profile banner'); ?>">
+                        <i class="fa fa-cloud-upload"></i>
+                    </a>
                     <a id="banner-image-upload-edit-button"
-                       style="<?php
-                       if (!$user->getProfileBannerImage()->hasImage()) {
-                           echo 'display: none;';
-                       }
-                       ?>"
-                       href="<?php echo Url::to(['/user/image/crop', 'userGuid' => $user->guid, 'type' => ImageController::TYPE_PROFILE_BANNER_IMAGE]); ?>"
-                       class="btn btn-info btn-sm" data-target="#globalModal" data-backdrop="static"><i
-                            class="fa fa-edit"></i></a>
+                       style="<?= (!$user->getProfileBannerImage()->hasImage()) ? 'display: none;' : '' ?>"
+                       href="<?= Url::to(['/user/image/crop', 'userGuid' => $user->guid, 'type' => ImageController::TYPE_PROFILE_BANNER_IMAGE]); ?>"
+                       class="btn btn-info btn-sm" data-target="#globalModal" data-backdrop="static" aria-label="<?= Yii::t('UserModule.base', 'Crop profile background'); ?>">
+                        <i class="fa fa-edit"></i>
+                    </a>
                         <?php
                         echo \humhub\widgets\ModalConfirm::widget(array(
                             'uniqueID' => 'modal_bannerimagedelete',
                             'linkOutput' => 'a',
+                            'ariaLabel' => Yii::t('UserModule.widgets_views_deleteBanner', 'Delete profile banner'),
                             'title' => Yii::t('UserModule.widgets_views_deleteBanner', '<strong>Confirm</strong> image deleting'),
                             'message' => Yii::t('UserModule.widgets_views_deleteBanner', 'Do you really want to delete your title image?'),
                             'buttonTrue' => Yii::t('UserModule.widgets_views_deleteBanner', 'Delete'),
@@ -111,7 +109,7 @@ if ($allowModifyProfileBanner || $allowModifyProfileImage) {
             <?php if ($allowModifyProfileImage) : ?>
                 <form class="fileupload" id="profilefileupload" action="" method="POST" enctype="multipart/form-data"
                       style="position: absolute; top: 0; left: 0; opacity: 0; height: 140px; width: 140px;">
-                    <input type="file" name="images[]">
+                    <input type="file" aria-hidden="true" name="images[]">
                 </form>
 
                 <div class="image-upload-loader" id="profile-image-upload-loader" style="padding-top: 60px;">
@@ -124,8 +122,9 @@ if ($allowModifyProfileBanner || $allowModifyProfileImage) {
                 </div>
 
                 <div class="image-upload-buttons" id="profile-image-upload-buttons">
-                    <a href="#" onclick="javascript:$('#profilefileupload input').click();" class="btn btn-info btn-sm"><i
-                            class="fa fa-cloud-upload"></i></a>
+                    <a href="#" onclick="javascript:$('#profilefileupload input').click();" class="btn btn-info btn-sm" aria-label="<?= Yii::t('UserModule.base', 'Upload profile image'); ?>">
+                        <i class="fa fa-cloud-upload"></i>
+                    </a>
                     <a id="profile-image-upload-edit-button"
                        style="<?php
                        if (!$user->getProfileImage()->hasImage()) {
@@ -133,12 +132,13 @@ if ($allowModifyProfileBanner || $allowModifyProfileImage) {
                        }
                        ?>"
                        href="<?php echo Url::to(['/user/image/crop', 'userGuid' => $user->guid, 'type' => ImageController::TYPE_PROFILE_IMAGE]); ?>"
-                       class="btn btn-info btn-sm" data-target="#globalModal" data-backdrop="static"><i
-                            class="fa fa-edit"></i></a>
+                       class="btn btn-info btn-sm" data-target="#globalModal" data-backdrop="static" aria-label="<?= Yii::t('UserModule.base', 'Crop profile image'); ?>">
+                            <i class="fa fa-edit"></i></a>
                         <?php
                         echo \humhub\widgets\ModalConfirm::widget(array(
                             'uniqueID' => 'modal_profileimagedelete',
                             'linkOutput' => 'a',
+                            'ariaLabel' => Yii::t('UserModule.base', 'Delete profile image'),
                             'title' => Yii::t('UserModule.widgets_views_deleteImage', '<strong>Confirm</strong> image deleting'),
                             'message' => Yii::t('UserModule.widgets_views_deleteImage', 'Do you really want to delete your profile image?'),
                             'buttonTrue' => Yii::t('UserModule.widgets_views_deleteImage', 'Delete'),
diff --git a/protected/humhub/widgets/BasePickerField.php b/protected/humhub/widgets/BasePickerField.php
index e2891045a0..3f3d3a69ab 100644
--- a/protected/humhub/widgets/BasePickerField.php
+++ b/protected/humhub/widgets/BasePickerField.php
@@ -318,6 +318,9 @@ abstract class BasePickerField extends InputWidget
         return $itemClass::find()->where([$this->itemKey => $selection])->all();
     }
 
+    /*
+     * @inheritdoc
+     */
     protected function getAttributes()
     {
         return [
@@ -325,6 +328,7 @@ abstract class BasePickerField extends InputWidget
             'size' => '1',
             'class' => 'form-control',
             'style' => 'width:100%',
+            'title' => $this->placeholder
         ];
     }
 
diff --git a/protected/humhub/widgets/LanguageChooser.php b/protected/humhub/widgets/LanguageChooser.php
index e4639988c9..2152d2436e 100644
--- a/protected/humhub/widgets/LanguageChooser.php
+++ b/protected/humhub/widgets/LanguageChooser.php
@@ -38,7 +38,7 @@ class LanguageChooser extends \yii\base\Widget
     {
         $model = new \humhub\models\forms\ChooseLanguage();
         $model->language = Yii::$app->language;
-        return $this->render('languageChooser', array('model' => $model, 'languages' => Yii::$app->i18n->getAllowedLanguages()));
+        return $this->render('languageChooser', ['model' => $model, 'languages' => Yii::$app->i18n->getAllowedLanguages()]);
     }
 
 }
diff --git a/protected/humhub/widgets/ModalConfirm.php b/protected/humhub/widgets/ModalConfirm.php
index 5d7e389361..51a72a8073 100644
--- a/protected/humhub/widgets/ModalConfirm.php
+++ b/protected/humhub/widgets/ModalConfirm.php
@@ -99,6 +99,8 @@ class ModalConfirm extends \yii\base\Widget
      * @var String contains optional JavaScript code to execute after modal has been made visible to the user
      */
     public $modalShownJS = "";
+    
+    public $ariaLabel = "";
 
     /**
      * Displays / Run the Widgets
@@ -110,6 +112,7 @@ class ModalConfirm extends \yii\base\Widget
                     'linkOutput' => $this->linkOutput,
                     'title' => $this->title,
                     'message' => $this->message,
+                    'ariaLabel' => $this->ariaLabel,
                     'buttonTrue' => $this->buttonTrue,
                     'buttonFalse' => $this->buttonFalse,
                     'class' => $this->cssClass,
diff --git a/protected/humhub/widgets/RichtextField.php b/protected/humhub/widgets/RichtextField.php
index 6bdbcce409..780d196977 100644
--- a/protected/humhub/widgets/RichtextField.php
+++ b/protected/humhub/widgets/RichtextField.php
@@ -149,6 +149,7 @@ class RichtextField extends JsWidget
         $inputOptions = $this->getAttributes();
         $inputOptions['id'] = $this->getId(true) . '_input';
         $inputOptions['style'] = 'display:none;color';
+        $inputOptions['title'] = $this->placeholder;
         unset($inputOptions['contenteditable']);
         $modelAttribute = $this->attribute;
 
diff --git a/protected/humhub/widgets/SiteLogo.php b/protected/humhub/widgets/SiteLogo.php
index 226ab19af8..13b70d9406 100644
--- a/protected/humhub/widgets/SiteLogo.php
+++ b/protected/humhub/widgets/SiteLogo.php
@@ -11,10 +11,7 @@ class SiteLogo extends \yii\base\Widget
 
     public function run()
     {
-
-        return $this->render('logo', array('logo' => new LogoImage(), 'place' => $this->place));
+        return $this->render('logo', ['logo' => new LogoImage(), 'place' => $this->place]);
     }
 
-}
-
-?>
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/protected/humhub/widgets/views/blueimpGallery.php b/protected/humhub/widgets/views/blueimpGallery.php
index 9503e2cce9..48a542ddfc 100644
--- a/protected/humhub/widgets/views/blueimpGallery.php
+++ b/protected/humhub/widgets/views/blueimpGallery.php
@@ -1,6 +1,6 @@
 <div id="blueimp-gallery" class="blueimp-gallery blueimp-gallery-controls">
     <div class="slides"></div>
-    <h3 class="title"></h3>
+    <h3 class="title">Hidden Gallery</h3>
     <a class="prev">‹</a>
     <a class="next">›</a>
     <a class="close">×</a>
diff --git a/protected/humhub/widgets/views/languageChooser.php b/protected/humhub/widgets/views/languageChooser.php
index ea0e9565a1..5fcfeda70e 100644
--- a/protected/humhub/widgets/views/languageChooser.php
+++ b/protected/humhub/widgets/views/languageChooser.php
@@ -4,10 +4,10 @@ use \humhub\compat\CActiveForm;
 ?>
 <div class="text text-center animated fadeIn">
     <?php if (count($languages) > 1) : ?>
-        <?php echo Yii::t('base', "Choose language:"); ?> &nbsp;
+        <?= Yii::t('base', "Choose language:"); ?> &nbsp;
         <div class="langSwitcher inline-block">
             <?php $form = CActiveForm::begin(['id' => 'choose-language-form']); ?>
-            <?php echo $form->dropDownList($model, 'language', $languages, array('onChange' => 'this.form.submit()')); ?>
+            <?= $form->dropDownList($model, 'language', $languages, ['onChange' => 'this.form.submit()', 'aria-label' => Yii::t('base', "Choose language:")]); ?>
             <?php CActiveForm::end(); ?>
         </div>
     <?php endif; ?>
diff --git a/protected/humhub/widgets/views/logo.php b/protected/humhub/widgets/views/logo.php
index 48774bbcf6..8f8492706d 100644
--- a/protected/humhub/widgets/views/logo.php
+++ b/protected/humhub/widgets/views/logo.php
@@ -4,27 +4,23 @@ use yii\helpers\Html;
 ?>
 <?php if ($place == "topMenu") : ?>
     <?php if ($logo->hasImage()) : ?>
-        <a class="navbar-brand hidden-xs" style="height: 50px; padding:5px;"
-           href="<?php echo Yii::$app->homeUrl; ?>">
-            <img class="img-rounded" src="<?php echo $logo->getUrl(); ?>"
-                 id="img-logo"/>
+        <a class="navbar-brand hidden-xs" style="height: 50px; padding:5px;" href="<?= Yii::$app->homeUrl; ?>">
+            <img class="img-rounded" src="<?= $logo->getUrl(); ?>" alt="<?= Yii::t('base', 'Logo of {appName}', ['appName' => Html::encode(Yii::$app->name)])?>" id="img-logo"/>
         </a>
     <?php endif; ?>
-    <a class="navbar-brand" style="<?php if ($logo->hasImage()) : ?>display:none;<?php endif; ?> "
-       href="<?php echo Yii::$app->homeUrl; ?>" id="text-logo">
-           <?php echo Html::encode(Yii::$app->name); ?>
+    <a class="navbar-brand" style="<?php if ($logo->hasImage()) : ?>display:none;<?php endif; ?> "  href="<?= Yii::$app->homeUrl; ?>" id="text-logo">
+           <?= Html::encode(Yii::$app->name); ?>
     </a>
 <?php endif; ?>
 
 <?php if ($place == "login") : ?>
     <?php if ($logo->hasImage()) : ?>
-        <a href="<?php echo Yii::$app->homeUrl; ?>">
-            <img class="img-rounded" src="<?php echo $logo->getUrl(); ?>"
-                 id="img-logo"/>
+        <a href="<?= Yii::$app->homeUrl; ?>">
+            <img class="img-rounded" src="<?= $logo->getUrl(); ?>" id="img-logo" alt="<?= Yii::t('base', 'Logo of {appName}', ['appName' => Html::encode(Yii::$app->name)]) ?>"/>
         </a>
         <br>
     <?php else: ?>
-        <h1 id="app-title" class="animated fadeIn"><?php echo Html::encode(Yii::$app->name); ?></h1>
+        <h1 id="app-title" class="animated fadeIn"><?= Html::encode(Yii::$app->name); ?></h1>
     <?php endif; ?>
 <?php endif; ?>
 
diff --git a/protected/humhub/widgets/views/modalConfirm.php b/protected/humhub/widgets/views/modalConfirm.php
index c219ac09b9..2cb51f7a69 100644
--- a/protected/humhub/widgets/views/modalConfirm.php
+++ b/protected/humhub/widgets/views/modalConfirm.php
@@ -1,8 +1,3 @@
-<?php
-
-
-?>
-
 <!-- add Tooltip to link -->
 <?php
 $tooltip = "";
@@ -27,7 +22,7 @@ if ($confirmJS != "") {
 <?php if ($linkOutput == 'button') { ?>
 
     <!-- create button element -->
-    <button class="<?php echo $class; ?> <?php if ($tooltip != "") : ?>tt<?php endif;?>" style="<?php echo $style; ?>"
+    <button class="<?php echo $class; ?> <?= ($ariaLabel) ? ' aria-label="'.$ariaLabel.'"' : '' ?> <?php if ($tooltip != "") : ?>tt<?php endif;?>" style="<?php echo $style; ?>"
             data-toggle="modal" data-target="#confirmModal_<?php echo $uniqueID; ?>" <?php echo $tooltip; ?>>
                 <?php echo $linkContent; ?>
     </button>
@@ -35,7 +30,7 @@ if ($confirmJS != "") {
 <?php } else if ($linkOutput == 'a') { ?>
 
     <!-- create normal link element -->
-    <a id="deleteLinkPost_<?php echo $uniqueID; ?>" class="<?php echo $class; ?> <?php if ($tooltip != "") : ?>tt<?php endif;?>" style="<?php echo $style; ?>" href="#"
+    <a id="deleteLinkPost_<?php echo $uniqueID; ?>" <?= ($ariaLabel) ? ' aria-label="'.$ariaLabel.'"' : '' ?> class="<?php echo $class; ?> <?php if ($tooltip != "") : ?>tt<?php endif;?>" style="<?php echo $style; ?>" href="#"
        data-toggle="modal" data-target="#confirmModal_<?php echo $uniqueID; ?>" <?php echo $tooltip; ?>>
            <?php echo $linkContent; ?>
     </a>
diff --git a/protected/humhub/widgets/views/panelMenu.php b/protected/humhub/widgets/views/panelMenu.php
index e543ba9ead..7c0cb6feb8 100644
--- a/protected/humhub/widgets/views/panelMenu.php
+++ b/protected/humhub/widgets/views/panelMenu.php
@@ -3,13 +3,18 @@ $this->registerJsFile("@web-static/js/panelMenu.js", ['position' => yii\web\View
 ?>
 <ul class="nav nav-pills preferences">
     <li class="dropdown ">
-        <a class="dropdown-toggle" data-toggle="dropdown" href="#"><i class="fa fa-angle-down"></i></a>
+        <a class="dropdown-toggle" data-toggle="dropdown" href="#" aria-label="<?= Yii::t('base', 'Toggle panel menu'); ?>" aria-haspopup="true"><i class="fa fa-angle-down"></i></a>
         <ul class="dropdown-menu pull-right">
-            <li><a href="javascript:togglePanelUp('<?php echo $id; ?>');" class="panel-collapse"><i
-                        class="fa fa-minus-square"></i> <?php echo Yii::t('base', 'Collapse'); ?></a></li>
-            <li><a href="javascript:togglePanelDown('<?php echo $id; ?>');" class="panel-expand" style="display:none;"><i
-                        class="fa fa-plus-square"></i> <?php echo Yii::t('base', 'Expand'); ?></a></li>
-
+            <li>
+                <a href="javascript:togglePanelUp('<?= $id; ?>');" class="panel-collapse">
+                    <i class="fa fa-minus-square"></i> <?= Yii::t('base', 'Collapse'); ?>
+                </a>
+            </li>
+            <li>
+                <a href="javascript:togglePanelDown('<?= $id; ?>');" class="panel-expand" style="display:none;">
+                    <i class="fa fa-plus-square"></i> <?= Yii::t('base', 'Expand'); ?>
+                </a>
+            </li>
             <?php
             echo $this->context->extraMenus;
             ?>
diff --git a/static/js/humhub/humhub.ui.modal.js b/static/js/humhub/humhub.ui.modal.js
index 702ec2e561..eb8b3ebd1e 100644
--- a/static/js/humhub/humhub.ui.modal.js
+++ b/static/js/humhub/humhub.ui.modal.js
@@ -56,7 +56,7 @@ humhub.module('ui.modal', function (module, require, $) {
      * Template for the modal splitted into different parts. Those can be overwritten my changing or overwriting module.template.
      */
     Modal.template = {
-        container: '<div class="modal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true" style="display: none; background:rgba(0,0,0,0.1)"><div class="modal-dialog"><div class="modal-content"></div></div></div>',
+        container: '<div class="modal" tabindex="-1" role="dialog" aria-hidden="true" style="display: none; background:rgba(0,0,0,0.1)"><div class="modal-dialog"><div class="modal-content"></div></div></div>',
         header: '<div class="modal-header"><button type="button" class="close" data-modal-close="true" aria-hidden="true">×</button><h4 class="modal-title"></h4></div>',
         body: '<div class="modal-body"></div>',
         footer: '<div class="modal-footer"></div>',
@@ -92,8 +92,16 @@ humhub.module('ui.modal', function (module, require, $) {
         });
 
         this.set(options);
-
-        this.$.attr('aria-labelledby', this.getTitleId());
+    };
+    
+    Modal.prototype.checkAriaLabel = function () {
+        var $title = this.$.find('.modal-title');
+        if($title.length) {
+            $title.attr('id', this.getTitleId());
+            this.$.attr('aria-labelledby', this.getTitleId());
+        } else {
+            this.$.removeAttr('aria-labelledby');
+        }
     };
 
     Modal.prototype.getTitleId = function () {
@@ -418,6 +426,7 @@ humhub.module('ui.modal', function (module, require, $) {
         this.$.empty().append(content);
         this.applyAdditions();
         this.$.find('input[type="text"]:visible, textarea:visible, [contenteditable="true"]:visible').first().focus();
+        this.checkAriaLabel();
         return this;
     };
 
diff --git a/static/js/humhub/humhub.ui.picker.js b/static/js/humhub/humhub.ui.picker.js
index fc0945499a..8856b4e149 100644
--- a/static/js/humhub/humhub.ui.picker.js
+++ b/static/js/humhub/humhub.ui.picker.js
@@ -184,11 +184,11 @@ humhub.module('ui.picker', function (module, require, $) {
         }
 
         if (this.$.children(':selected').length >= this.$.data('maximum-selection-length')) {
-            this.$.data('select2').$selection.find('input').attr('placeholder', null);
+            this.$.data('select2').$selection.find('input').attr('placeholder', null).attr('title', null);
         } else if (this.$.val()) {
-            this.$.data('select2').$selection.find('input').attr('placeholder', this.options.placeholderMore);
+            this.$.data('select2').$selection.find('input').attr('placeholder', this.options.placeholderMore).attr('title', this.options.placeholderMore);
         } else {
-            this.$.data('select2').$selection.find('input').attr('placeholder', this.options.placeholder);
+            this.$.data('select2').$selection.find('input').attr('placeholder', this.options.placeholder).attr('title', this.options.placeholderMore);
         }
     };