diff --git a/src/Form/AchievementEntityForm.php b/src/Form/AchievementEntityForm.php
index 0e2d795..7ea10db 100755
--- a/src/Form/AchievementEntityForm.php
+++ b/src/Form/AchievementEntityForm.php
@@ -124,7 +124,7 @@ class AchievementEntityForm extends EntityForm {
         // directory; stream wrappers are not end-user friendly.
         $original_path = $element['#default_value'];
         $friendly_path = NULL;
-        if (\Drupal::service('file_system')->uriScheme($original_path) == 'public') {
+        if (\Drupal::service('stream_wrapper_manager')->getScheme($original_path) == 'public') {
           $friendly_path = \Drupal::service('stream_wrapper_manager')->getTarget($original_path);
           $element['#default_value'] = $friendly_path;
         }
@@ -139,7 +139,7 @@ class AchievementEntityForm extends EntityForm {
 
         $element['#description'] = t('Examples: <code>@implicit-public-file</code> (for a file in the public filesystem), <code>@explicit-file</code>, or <code>@local-file</code>.', [
           '@implicit-public-file' => isset($friendly_path) ? $friendly_path : $default,
-          '@explicit-file' => \Drupal::service('file_system')->uriScheme($original_path) !== FALSE ? $original_path : 'public://' . $default,
+          '@explicit-file' => \Drupal::service('stream_wrapper_manager')->getScheme($original_path) !== FALSE ? $original_path : 'public://' . $default,
           '@local-file' => $local_file,
         ]);
       }
@@ -206,7 +206,7 @@ class AchievementEntityForm extends EntityForm {
       return $path;
     }
     // Prepend 'public://' for relative file paths within public filesystem.
-    if (\Drupal::service('file_system')->uriScheme($path) === FALSE) {
+    if (\Drupal::service('stream_wrapper_manager')->getScheme($path) === FALSE) {
       $path = 'public://' . $path;
     }
     if (is_file($path)) {
-- 
2.18.0