diff --git a/config/schema/metatag.metatag_tag.schema.yml b/config/schema/metatag.metatag_tag.schema.yml
index 76b8202..7651a6c 100644
--- a/config/schema/metatag.metatag_tag.schema.yml
+++ b/config/schema/metatag.metatag_tag.schema.yml
@@ -36,11 +36,8 @@ metatag.metatag_tag.referrer:
   type: label
   label: 'Referrer policy'
 metatag.metatag_tag.robots:
-  type: sequence
+  type: label
   label: 'Robots'
-  sequence:
-     type: boolean
-     translatable: true
 metatag.metatag_tag.shortlink:
   type: label
   label: 'Shortlink'
diff --git a/metatag.api.php b/metatag.api.php
index 058a1c9..7f3c82c 100644
--- a/metatag.api.php
+++ b/metatag.api.php
@@ -30,10 +30,10 @@ function hook_metatag_route_entity(\Drupal\Core\Routing\RouteMatchInterface $rou
  *
  * @param array $metatags
  *   The special metatags to be added to the page.
- * @param \Drupal\Core\Entity\EntityInterface $entity
- *   The entity used for token replacements.
+ * @param array $context
+ *   The context, containing the entity used for token replacements.
  */
-function hook_metatags_alter(array &$metatags, \Drupal\Core\Entity\EntityInterface $entity) {
+function hook_metatags_alter(array &$metatags, array $context) {
   // Exclude metatags on frontpage.
   if (\Drupal::service('path.matcher')->isFrontPage()) {
     $metatags = NULL;
diff --git a/metatag_views/src/MetatagViewsValuesCleanerTrait.php b/metatag_views/src/MetatagViewsValuesCleanerTrait.php
index 4a1176a..a13f8a2 100644
--- a/metatag_views/src/MetatagViewsValuesCleanerTrait.php
+++ b/metatag_views/src/MetatagViewsValuesCleanerTrait.php
@@ -2,20 +2,21 @@
 
 namespace Drupal\metatag_views;
 
-use Drupal\views\ViewEntityInterface;
-
-
+/**
+ * Collection of helper methods when handling raw tag values.
+ */
 trait MetatagViewsValuesCleanerTrait {
+
   /**
    * Clears the metatag form state values from illegal elements.
    *
    * @param array $metatags
-   *  Array of values to submit.
+   *   Array of values to submit.
    *
    * @return array
-   *  Filtered metatag array.
+   *   Filtered metatag array.
    */
-  public function clearMetatagViewsDisallowedValues($metatags) {
+  public function clearMetatagViewsDisallowedValues(array $metatags) {
     // Get all legal tags.
     $tags = $this->metatagManager->sortedTags();
 
@@ -25,8 +26,11 @@ trait MetatagViewsValuesCleanerTrait {
     return $metatags;
   }
 
+  /**
+   * Removes tags that are empty.
+   */
   public function removeEmptyTags($metatags) {
-    $metatags = array_filter($metatags, function($value) {
+    $metatags = array_filter($metatags, function ($value) {
       if (is_array($value)) {
         return count(array_filter($value)) > 0;
       }
diff --git a/metatag_views/src/Plugin/views/display_extender/MetatagDisplayExtender.php b/metatag_views/src/Plugin/views/display_extender/MetatagDisplayExtender.php
index deb6e5b..c9c1d11 100644
--- a/metatag_views/src/Plugin/views/display_extender/MetatagDisplayExtender.php
+++ b/metatag_views/src/Plugin/views/display_extender/MetatagDisplayExtender.php
@@ -1,17 +1,12 @@
 <?php
 
-/**
- * @file
- * Contains \Drupal\metatag_views\Plugin\views\display_extender\MetatagDisplayExtender.
- */
-
 namespace Drupal\metatag_views\Plugin\views\display_extender;
 
-use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Form\FormStateInterface;
 use Drupal\metatag\MetatagManagerInterface;
-use Drupal\metatag_views\MetatagViewsValuesCleanerTrait;
+use Drupal\metatag\MetatagTagPluginManager;
 use Drupal\views\Plugin\views\display_extender\DisplayExtenderPluginBase;
-use Drupal\Core\Form\FormStateInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * Metatag display extender plugin.
@@ -26,11 +21,56 @@ use Drupal\Core\Form\FormStateInterface;
  * )
  */
 class MetatagDisplayExtender extends DisplayExtenderPluginBase {
-  use MetatagViewsValuesCleanerTrait;
-  /** @var  MetatagManagerInterface */
+
+  /**
+   * The metatag manager.
+   *
+   * @var \Drupal\metatag\MetatagManagerInterface
+   */
   protected $metatagManager;
 
   /**
+   * The plugin manager for metatag tags.
+   *
+   * @var \Drupal\metatag\MetatagTagPluginManager
+   */
+  protected $metatagTagManager;
+
+  /**
+   * Constructs the plugin.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param Drupal\metatag\MetatagTagPluginManager $metatag_plugin_manager
+   *   The plugin manager for metatag tags.
+   * @param Drupal\metatag\MetatagManagerInterface $metatag_manager
+   *   The metatag manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, MetatagTagPluginManager $metatag_plugin_manager, MetatagManagerInterface $metatag_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->metatagTagManager = $metatag_plugin_manager;
+    $this->metatagManager = $metatag_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('plugin.manager.metatag.tag'),
+      $container->get('metatag.manager')
+    );
+  }
+
+  /**
    * Provide a form to edit options for this plugin.
    */
   public function buildOptionsForm(&$form, FormStateInterface $form_state) {
@@ -40,7 +80,6 @@ class MetatagDisplayExtender extends DisplayExtenderPluginBase {
       $metatags = $this->getMetatags();
 
       // Build/inject the Metatag form.
-      $this->metatagManager = \Drupal::service('metatag.manager');
       $form['metatags'] = $this->metatagManager->form($metatags, $form, ['view']);
     }
   }
@@ -56,10 +95,19 @@ class MetatagDisplayExtender extends DisplayExtenderPluginBase {
    */
   public function submitOptionsForm(&$form, FormStateInterface $form_state) {
     if ($form_state->get('section') == 'metatags') {
-      $metatags = $form_state->getValues();
-      // Remove the unnecessary elements from values array.
-      $metatags = $this->clearMetatagViewsDisallowedValues($metatags);
-      $this->options['metatags'] = $metatags;
+      // Process submitted metatag values and remove empty tags.
+      $tag_values = [];
+      $metatags = $form_state->cleanValues()->getValues();
+      foreach ($metatags as $tag_id => $tag_value) {
+        // Some plugins need to process form input before storing it.
+        // Hence, we set it and then get it.
+        $tag = $this->metatagTagManager->createInstance($tag_id);
+        $tag->setValue($tag_value);
+        if (!empty($tag->value())) {
+          $tag_values[$tag_id] = $tag->value();
+        }
+      }
+      $this->options['metatags'] = $tag_values;
     }
   }
 
@@ -93,14 +141,16 @@ class MetatagDisplayExtender extends DisplayExtenderPluginBase {
   }
 
   /**
-   * Static member function to list which sections are defaultable
-   * and what items each section contains.
+   * Lists defaultable sections and items contained in each section.
    */
   public function defaultableSections(&$sections, $section = NULL) {
   }
 
   /**
    * Identify whether or not the current display has custom meta tags defined.
+   *
+   * @return bool
+   *   Whether or not the view has overridden metatags.
    */
   protected function hasMetatags() {
     $metatags = $this->getMetatags();
@@ -124,7 +174,14 @@ class MetatagDisplayExtender extends DisplayExtenderPluginBase {
     return $metatags;
   }
 
-  public function setMetatags($metatags) {
+  /**
+   * Sets the metatags for the given view.
+   *
+   * @param array $metatags
+   *   Metatag arrays as suitable for storage.
+   */
+  public function setMetatags(array $metatags) {
     $this->options['metatags'] = $metatags;
   }
+
 }
diff --git a/src/Tests/MetatagAdminTest.php b/src/Tests/MetatagAdminTest.php
index 9675ea6..dd3f661 100644
--- a/src/Tests/MetatagAdminTest.php
+++ b/src/Tests/MetatagAdminTest.php
@@ -121,7 +121,7 @@ class MetatagAdminTest extends WebTestBase {
     $robots_values = ['index', 'follow', 'noydir'];
     $values = [];
     foreach ($robots_values as $value) {
-      $values['robots[' . $value . ']'] = 1;
+      $values['robots[' . $value . ']'] = TRUE;
     }
     $this->drupalPostForm(NULL, $values, 'Save');
     $this->assertText('Saved the Global Metatag defaults.');
diff --git a/src/Tests/MetatagTagsTest.php b/src/Tests/MetatagTagsTest.php
index 7f036fb..52f6306 100644
--- a/src/Tests/MetatagTagsTest.php
+++ b/src/Tests/MetatagTagsTest.php
@@ -154,7 +154,7 @@ class MetatagTagsTest extends MetatagTagsTestBase {
    * Implements {meta_tag_name}_test_value() for 'robots'.
    */
   public function robots_test_value() {
-    return 1;
+    return TRUE;
   }
 
   /**