diff -u b/core/lib/Drupal/Core/Field/MediaFormatterTrait.php b/core/lib/Drupal/Core/Field/MediaFormatterTrait.php
--- b/core/lib/Drupal/Core/Field/MediaFormatterTrait.php
+++ b/core/lib/Drupal/Core/Field/MediaFormatterTrait.php
@@ -2,10 +2,8 @@
 
 namespace Drupal\Core\Field;
 
-use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Template\Attribute;
-use Drupal\Core\Field\MediaFormatterTrait;
 
 /**
  * Useful methods for media formatters.
@@ -18,0 +17,157 @@
+   */
+  public static function defaultSettings() {
+    return [
+      'controls' => TRUE,
+      'autoplay' => FALSE,
+      'loop' => FALSE,
+      'multiple_file_display_type' => 'tags',
+    ] + parent::defaultSettings();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsForm(array $form, FormStateInterface $form_state) {
+    return [
+      'controls' => [
+        '#title' => $this->t('Show playback controls'),
+        '#type' => 'checkbox',
+        '#default_value' => $this->getSetting('controls'),
+      ],
+      'autoplay' => [
+        '#title' => $this->t('Autoplay'),
+        '#type' => 'checkbox',
+        '#default_value' => $this->getSetting('autoplay'),
+      ],
+      'loop' => [
+        '#title' => $this->t('Loop'),
+        '#type' => 'checkbox',
+        '#default_value' => $this->getSetting('loop'),
+      ],
+      'multiple_file_display_type' => [
+        '#title' => $this->t('Display of multiple files'),
+        '#type' => 'radios',
+        '#options' => [
+          'tags' => $this->t('Use multiple @tag tags, each with a single source.', ['@tag' => '<' . $this->getHtmlTag() . '>']),
+          'sources' => $this->t('Use multiple sources within a single @tag tag.', ['@tag' => '<' . $this->getHtmlTag() . '>']),
+        ],
+        '#default_value' => $this->getSetting('multiple_file_display_type'),
+      ],
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsSummary() {
+    $summary = [];
+    $summary[] = $this->t('Playback controls: %controls', ['%controls' => $this->getSetting('controls') ? $this->t('visible') : $this->t('hidden')]);
+    $summary[] = $this->t('Autoplay: %autoplay', ['%autoplay' => $this->getSetting('autoplay') ? $this->t('yes') : $this->t('no')]);
+    $summary[] = $this->t('Loop: %loop', ['%loop' => $this->getSetting('loop') ? $this->t('yes') : $this->t('no')]);
+    switch ($this->getSetting('multiple_file_display_type')) {
+      case 'tags':
+        $summary[] = $this->t('Multiple file display: Multiple HTML tags');
+        break;
+
+      case 'sources':
+        $summary[] = $this->t('Multiple file display: One HTML tag with multiple sources');
+        break;
+    }
+    return $summary;
+  }
+
+  /**
+   * Gets the HTML tag for the formatter.
+   *
+   * @return string
+   *   The HTML tag of this formatter.
+   */
+  protected function getHtmlTag() {
+    return static::getMediaType();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items, $langcode) {
+    $elements = [];
+
+    $source_files = $this->getSourceFiles($items, $langcode);
+    if (empty($source_files)) {
+      return $elements;
+    }
+
+    $attributes = $this->prepareAttributes();
+    foreach ($source_files as $delta => $files) {
+      $elements[$delta] = [
+        '#theme' => 'file_' . $this->getHtmlTag(),
+        '#attributes' => $attributes,
+        '#files' => $files,
+      ];
+    }
+    return $elements;
+  }
+
+  /**
+   * Prepare the attributes according to the settings.
+   *
+   * @param string[] $additional_attributes
+   *   Additional attributes to be applied to the HTML element. Attribute names
+   *   will be used as key and value in the HTML element.
+   *
+   * @return \Drupal\Core\Template\Attribute
+   *   Container with all the attributes for the HTML tag.
+   */
+  protected function prepareAttributes(array $additional_attributes = []) {
+    $attributes = new Attribute();
+    foreach (['controls', 'autoplay', 'loop'] + $additional_attributes as $attribute) {
+      if ($this->getSetting($attribute)) {
+        $attributes->setAttribute($attribute, $attribute);
+      }
+    }
+    return $attributes;
+  }
+
+    /**
+   * Check if given MIME type applies to the media type of the formatter.
+   *
+   * @param string $mime_type
+   *   The complete MIME type.
+   *
+   * @return bool
+   *   TRUE if the MIME type applies, FALSE otherwise.
+   */
+  protected static function mimeTypeApplies($mime_type) {
+    list($type) = explode('/', $mime_type, 2);
+    return $type === static::getMediaType();
+  }
+
+}
+<?php
+
+namespace Drupal\file\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Field\EntityReferenceFieldItemListInterface;
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Template\Attribute;
+
+/**
+ * Base class for media file formatter.
+ */
+abstract class FileMediaFormatterBase extends FileFormatterBase implements FileMediaFormatterInterface {
+
+  /**
+   * Gets the HTML tag for the formatter.
+   *
+   * @return string
+   *   The HTML tag of this formatter.
+   */
+  protected function getHtmlTag() {
+    return static::getMediaType();
+  }
+
+  /**
+   * {@inheritdoc}
@@ -63,0 +219,21 @@
+  public static function isApplicable(FieldDefinitionInterface $field_definition) {
+    if (!parent::isApplicable($field_definition)) {
+      return FALSE;
+    }
+    /** @var \Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface $extension_mime_type_guesser */
+    $extension_mime_type_guesser = \Drupal::service('file.mime_type.guesser.extension');
+    $extension_list = array_filter(preg_split('/\s+/', $field_definition->getSetting('file_extensions')));
+
+    foreach ($extension_list as $extension) {
+      $mime_type = $extension_mime_type_guesser->guess('fakedFile.' . $extension);
+
+      if (static::mimeTypeApplies($mime_type)) {
+        return TRUE;
+      }
+    }
+    return FALSE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
@@ -80,14 +256,4 @@
 
   /**
-   * Gets the HTML tag for the formatter.
-   *
-   * @return string
-   *   The HTML tag of this formatter.
-   */
-  protected function getHtmlTag() {
-    return static::getMediaType();
-  }
-
-  /**
    * {@inheritdoc}
    */
@@ -102,11 +268,19 @@
     $attributes = $this->prepareAttributes();
     foreach ($source_files as $delta => $files) {
       $elements[$delta] = [
-        '#theme' => 'file_' . $this->getHtmlTag(),
+        '#theme' => $this->getPluginId(),
         '#attributes' => $attributes,
         '#files' => $files,
+        '#cache' => ['tags' => []],
       ];
+
+      $cache_tags = [];
+      foreach ($files as $file) {
+        $cache_tags = Cache::mergeTags($cache_tags, $file['file']->getCacheTags());
+      }
+      $elements[$delta]['#cache']['tags'] = $cache_tags;
     }
+
     return $elements;
   }
 
@@ -132,2 +306,60 @@
 
+  /**
+   * Check if given MIME type applies to the media type of the formatter.
+   *
+   * @param string $mime_type
+   *   The complete MIME type.
+   *
+   * @return bool
+   *   TRUE if the MIME type applies, FALSE otherwise.
+   */
+  protected static function mimeTypeApplies($mime_type) {
+    list($type) = explode('/', $mime_type, 2);
+    return $type === static::getMediaType();
+  }
+
+  /**
+   * Gets source files with attributes.
+   *
+   * @param \Drupal\Core\Field\EntityReferenceFieldItemListInterface $items
+   *   The item list.
+   * @param string $langcode
+   *   The language code of the referenced entities to display.
+   *
+   * @return array
+   *   Numerically indexed array, which again contains an associative array with
+   *   the following key/values:
+   *     - file => \Drupal\file\Entity\File
+   *     - source_attributes => \Drupal\Core\Template\Attribute
+   */
+  protected function getSourceFiles(EntityReferenceFieldItemListInterface $items, $langcode) {
+    $source_files = [];
+    // Because we can have the files grouped in a single media tag, we do a
+    // grouping in case the multiple file behavior is not 'tags'.
+    /** @var \Drupal\file\Entity\File $file */
+    foreach ($this->getEntitiesToView($items, $langcode) as $file) {
+      if (static::mimeTypeApplies($file->getMimeType())) {
+        $source_attributes = new Attribute();
+        $source_attributes
+          ->setAttribute('src', file_url_transform_relative(file_create_url($file->getFileUri())))
+          ->setAttribute('type', $file->getMimeType());
+        if ($this->getSetting('multiple_file_display_type') === 'tags') {
+          $source_files[] = [
+            [
+              'file' => $file,
+              'source_attributes' => $source_attributes,
+            ],
+          ];
+        }
+        else {
+          $source_files[0][] = [
+            'file' => $file,
+            'source_attributes' => $source_attributes,
+          ];
+        }
+      }
+    }
+    return $source_files;
+  }
+
 }
only in patch2:
unchanged:
--- a/core/modules/file/src/Plugin/Field/FieldFormatter/FileMediaFormatterBase.php
+++ b/core/modules/file/src/Plugin/Field/FieldFormatter/FileMediaFormatterBase.php
@@ -6,6 +6,7 @@
 use Drupal\Core\Field\EntityReferenceFieldItemListInterface;
 use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\MediaFormatterTrait;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Template\Attribute;
 
@@ -14,59 +15,7 @@
  */
 abstract class FileMediaFormatterBase extends FileFormatterBase implements FileMediaFormatterInterface {
 
-  /**
-   * Gets the HTML tag for the formatter.
-   *
-   * @return string
-   *   The HTML tag of this formatter.
-   */
-  protected function getHtmlTag() {
-    return static::getMediaType();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function defaultSettings() {
-    return [
-      'controls' => TRUE,
-      'autoplay' => FALSE,
-      'loop' => FALSE,
-      'multiple_file_display_type' => 'tags',
-    ] + parent::defaultSettings();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function settingsForm(array $form, FormStateInterface $form_state) {
-    return [
-      'controls' => [
-        '#title' => $this->t('Show playback controls'),
-        '#type' => 'checkbox',
-        '#default_value' => $this->getSetting('controls'),
-      ],
-      'autoplay' => [
-        '#title' => $this->t('Autoplay'),
-        '#type' => 'checkbox',
-        '#default_value' => $this->getSetting('autoplay'),
-      ],
-      'loop' => [
-        '#title' => $this->t('Loop'),
-        '#type' => 'checkbox',
-        '#default_value' => $this->getSetting('loop'),
-      ],
-      'multiple_file_display_type' => [
-        '#title' => $this->t('Display of multiple files'),
-        '#type' => 'radios',
-        '#options' => [
-          'tags' => $this->t('Use multiple @tag tags, each with a single source.', ['@tag' => '<' . $this->getHtmlTag() . '>']),
-          'sources' => $this->t('Use multiple sources within a single @tag tag.', ['@tag' => '<' . $this->getHtmlTag() . '>']),
-        ],
-        '#default_value' => $this->getSetting('multiple_file_display_type'),
-      ],
-    ];
-  }
+  use MediaFormatterTrait;
 
   /**
    * {@inheritdoc}
@@ -89,26 +38,6 @@ public static function isApplicable(FieldDefinitionInterface $field_definition)
     return FALSE;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function settingsSummary() {
-    $summary = [];
-    $summary[] = $this->t('Playback controls: %controls', ['%controls' => $this->getSetting('controls') ? $this->t('visible') : $this->t('hidden')]);
-    $summary[] = $this->t('Autoplay: %autoplay', ['%autoplay' => $this->getSetting('autoplay') ? $this->t('yes') : $this->t('no')]);
-    $summary[] = $this->t('Loop: %loop', ['%loop' => $this->getSetting('loop') ? $this->t('yes') : $this->t('no')]);
-    switch ($this->getSetting('multiple_file_display_type')) {
-      case 'tags':
-        $summary[] = $this->t('Multiple file display: Multiple HTML tags');
-        break;
-
-      case 'sources':
-        $summary[] = $this->t('Multiple file display: One HTML tag with multiple sources');
-        break;
-    }
-    return $summary;
-  }
-
   /**
    * {@inheritdoc}
    */
@@ -135,44 +64,9 @@ public function viewElements(FieldItemListInterface $items, $langcode) {
       }
       $elements[$delta]['#cache']['tags'] = $cache_tags;
     }
-
     return $elements;
   }
 
-  /**
-   * Prepare the attributes according to the settings.
-   *
-   * @param string[] $additional_attributes
-   *   Additional attributes to be applied to the HTML element. Attribute names
-   *   will be used as key and value in the HTML element.
-   *
-   * @return \Drupal\Core\Template\Attribute
-   *   Container with all the attributes for the HTML tag.
-   */
-  protected function prepareAttributes(array $additional_attributes = []) {
-    $attributes = new Attribute();
-    foreach (['controls', 'autoplay', 'loop'] + $additional_attributes as $attribute) {
-      if ($this->getSetting($attribute)) {
-        $attributes->setAttribute($attribute, $attribute);
-      }
-    }
-    return $attributes;
-  }
-
-  /**
-   * Check if given MIME type applies to the media type of the formatter.
-   *
-   * @param string $mime_type
-   *   The complete MIME type.
-   *
-   * @return bool
-   *   TRUE if the MIME type applies, FALSE otherwise.
-   */
-  protected static function mimeTypeApplies($mime_type) {
-    list($type) = explode('/', $mime_type, 2);
-    return $type === static::getMediaType();
-  }
-
   /**
    * Gets source files with attributes.
    *