diff --git a/js/dropdown-widget.js b/js/dropdown-widget.js
index 5d599f1..0da8a5a 100644
--- a/js/dropdown-widget.js
+++ b/js/dropdown-widget.js
@@ -29,6 +29,10 @@
       var $links = $ul.find('.facet-item a');
       var $dropdown = $('<select class="facets-dropdown" />').data($ul.data());
 
+      if ($ul.hasClass('js-multiple-select')) {
+        $dropdown.attr('multiple', 'multiple');
+      }
+
       var id = $(this).data('drupal-facet-id');
       var default_option_label = settings.facets.dropdown_widget[id]['facet-default-option-label'];
       // Add empty text option first.
diff --git a/src/Plugin/facets/widget/DropdownWidget.php b/src/Plugin/facets/widget/DropdownWidget.php
index b2e2fa9..ff370fc 100644
--- a/src/Plugin/facets/widget/DropdownWidget.php
+++ b/src/Plugin/facets/widget/DropdownWidget.php
@@ -32,6 +32,9 @@ class DropdownWidget extends WidgetPluginBase {
   public function build(FacetInterface $facet) {
     $build = parent::build($facet);
     $build['#attributes']['class'][] = 'js-facets-dropdown-links';
+    if (!$facet->getShowOnlyOneResult()) {
+      $build['#attributes']['class'][] = 'js-multiple-select';
+    }
     $build['#attached']['drupalSettings']['facets']['dropdown_widget'][$facet->id()]['facet-default-option-label'] = $this->getConfiguration()['default_option_label'];
     $build['#attached']['library'][] = 'facets/drupal.facets.dropdown-widget';
     return $build;
@@ -43,11 +46,6 @@ class DropdownWidget extends WidgetPluginBase {
   public function buildConfigurationForm(array $form, FormStateInterface $form_state, FacetInterface $facet) {
     $config = $this->getConfiguration();
 
-    $message = $this->t('To achieve the standard behavior of a dropdown, you need to enable the facet setting below <em>"Ensure that only one result can be displayed"</em>.');
-    $form['warning'] = [
-      '#markup' => '<div class="messages messages--warning">' . $message . '</div>',
-    ];
-
     $form += parent::buildConfigurationForm($form, $form_state, $facet);
 
     $form['default_option_label'] = [