css/entity_embed.media_library.dialog.css  | 10 ++++++++++
 entity_embed.libraries.yml                 |  6 ++++++
 src/Plugin/CKEditorPlugin/DrupalEntity.php |  9 +++++++++
 3 files changed, 25 insertions(+)

diff --git a/css/entity_embed.media_library.dialog.css b/css/entity_embed.media_library.dialog.css
new file mode 100644
index 0000000..35307a3
--- /dev/null
+++ b/css/entity_embed.media_library.dialog.css
@@ -0,0 +1,10 @@
+/**
+ * @file
+ * Styles for Media Library's modal windows.
+ */
+
+/* Work around dialogOptions imposed by Drupal.ckeditor.openDialog(). */
+.ui-dialog--narrow.media-library-widget-modal {
+  width: 75% !important;
+  max-width: none;
+}
diff --git a/entity_embed.libraries.yml b/entity_embed.libraries.yml
index 5eca8e7..da74e69 100644
--- a/entity_embed.libraries.yml
+++ b/entity_embed.libraries.yml
@@ -8,3 +8,9 @@ drupal.entity_embed.dialog:
   dependencies:
     - core/drupal
     - core/jquery
+
+media_library.dialog:
+  version: VERSION
+  css:
+    theme:
+      css/entity_embed.media_library.dialog.css: {}
diff --git a/src/Plugin/CKEditorPlugin/DrupalEntity.php b/src/Plugin/CKEditorPlugin/DrupalEntity.php
index 8dd1ecc..948b93b 100644
--- a/src/Plugin/CKEditorPlugin/DrupalEntity.php
+++ b/src/Plugin/CKEditorPlugin/DrupalEntity.php
@@ -36,6 +36,15 @@ class DrupalEntity extends EmbedCKEditorPluginBase {
     return drupal_get_path('module', 'entity_embed') . '/js/plugins/drupalentity/plugin.js';
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getLibraries(Editor $editor) {
+    $libraries = parent::getLibraries($editor);
+    $libraries[] = 'entity_embed/media_library.dialog';
+    return $libraries;
+  }
+
   /**
    * {@inheritdoc}
    */