diff --git a/js/superfish.js b/js/superfish.js
index a99ec5d..0a98e32 100644
--- a/js/superfish.js
+++ b/js/superfish.js
@@ -3,6 +3,20 @@
  * The Superfish Drupal Behavior to apply the Superfish jQuery plugin to lists.
  */
 
+(function (Drupal, $, once) {
+  Drupal.behaviors.myfeature = {
+    attach(context) {
+      // The once call is wrapped in $() to allow the usual jQuery chaining.
+      const $elements =  $(once('myfeature', '[data-myfeature]', context));
+      // `$elements` is always a jQuery object.
+      $elements.each(processingCallback);
+    }
+  };
+
+  function processingCallback(index, value) {}
+}(Drupal, jQuery, once));
+
+
 (function ($, Drupal, drupalSettings) {
 
   'use strict';
diff --git a/superfish.info.yml b/superfish.info.yml
index 3cc3902..651e875 100644
--- a/superfish.info.yml
+++ b/superfish.info.yml
@@ -3,4 +3,4 @@ type: module
 description: 'Adds jQuery Superfish plugin to menu blocks.'
 package: User interface
 core: 8.x
-core_version_requirement: ^8 || ^9
+core_version_requirement: ^8 || ^9 || ^10
diff --git a/superfish.module b/superfish.module
index b49ef31..86f7330 100644
--- a/superfish.module
+++ b/superfish.module
@@ -71,7 +71,7 @@ function superfish_library_info_build() {
           'core/jquery',
           'core/drupal',
           'core/drupalSettings',
-          'core/jquery.once',
+          'core/once',
         ],
       ],
       'init' => [
@@ -198,16 +198,10 @@ function superfish_library_path($library = 'superfish') {
   $directory = FALSE;
   // Ensure the Libraries API module is installed and working.
   if (function_exists('libraries_get_path')) {
-    $directory = libraries_get_path($library);
+    $directory = 'libraries/' . $library;
     if ($directory) {
       return $directory;
     }
-    elseif (ucfirst($library) !== $library) {
-      $directory = libraries_get_path(ucfirst($library));
-      if ($directory) {
-        return $directory;
-      }
-    }
   }
   // Otherwise use the default directory.
   if (\Drupal::hasContainer()) {
@@ -244,17 +238,9 @@ function superfish_library_path($library = 'superfish') {
  * Verifies Superfish library is present.
  */
 function superfish_library_check() {
-  if (function_exists('libraries_get_libraries')) {
-    $library = libraries_get_libraries();
-    if (isset($library['superfish']) || isset($library['Superfish'])) {
-      return TRUE;
-    }
-  }
-  else {
-    $directory = superfish_library_path();
-    if ($directory && file_exists($directory . '/superfish.js')) {
-      return TRUE;
-    }
+  $directory = superfish_library_path();
+  if ($directory && file_exists($directory . '/superfish.js')) {
+    return TRUE;
   }
   return FALSE;
 }
diff --git a/templates/superfish-menu-items.html.twig b/templates/superfish-menu-items.html.twig
index f396137..9d744ae 100644
--- a/templates/superfish-menu-items.html.twig
+++ b/templates/superfish-menu-items.html.twig
@@ -20,7 +20,7 @@
 #}
 
 {% set classes = [] %}
-{% spaceless %}
+{% apply spaceless %}
 {% for item in menu_items %}
 
   {% if item.children is not empty %}
@@ -52,4 +52,4 @@
   </li>
 
 {% endfor %}
-{% endspaceless %}
+{% endapply %}