diff --git a/.github/workflows/moodle-ci.yml b/.github/workflows/moodle-ci.yml
index 75e5a44..459497e 100644
--- a/.github/workflows/moodle-ci.yml
+++ b/.github/workflows/moodle-ci.yml
@@ -31,7 +31,7 @@ jobs:
       fail-fast: false
       matrix:
         php: ['7.4', '8.0', '8.1', '8.2']
-        moodle-branch: [MOODLE_311_STABLE, MOODLE_400_STABLE, MOODLE_401_STABLE, MOODLE_402_STABLE, MOODLE_403_STABLE]
+        moodle-branch: [MOODLE_401_STABLE, MOODLE_402_STABLE, MOODLE_403_STABLE]
         database: [pgsql, mariadb]
         # See: https://moodledev.io/general/development/policies/php
         exclude:
@@ -41,14 +41,6 @@ jobs:
             moodle-branch: MOODLE_403_STABLE
           - php: '8.0'
             moodle-branch: MOODLE_403_STABLE
-          - php: '8.1'
-            moodle-branch: MOODLE_311_STABLE
-          - php: '8.1'
-            moodle-branch: MOODLE_400_STABLE
-          - php: '8.2'
-            moodle-branch: MOODLE_311_STABLE
-          - php: '8.2'
-            moodle-branch: MOODLE_400_STABLE
           - php: '8.2'
             moodle-branch: MOODLE_401_STABLE
 
diff --git a/classes/course_files.php b/classes/course_files.php
index 7f38109..7c50a29 100644
--- a/classes/course_files.php
+++ b/classes/course_files.php
@@ -146,14 +146,9 @@ public function get_file_list($offset, $limit) {
             $sqlwhere .= ' AND ' . $this->get_sql_mimetype($this->filterfiletype, true);
         }
 
-        if (class_exists('\core_user\fields')) {
-            $usernameselect = implode(', ', array_map(function($field) {
-                return 'u.' . $field;
-            }, \core_user\fields::get_name_fields()));
-        } else {
-            // For compatibility with Moodle 3.9.
-            $usernameselect = get_all_user_name_fields(true, 'u');
-        }
+        $usernameselect = implode(', ', array_map(function($field) {
+            return 'u.' . $field;
+        }, \core_user\fields::get_name_fields()));
 
         $sql = "FROM {files} f
            LEFT JOIN {context} c ON (c.id = f.contextid)
diff --git a/version.php b/version.php
index f68f876..f9cda0c 100644
--- a/version.php
+++ b/version.php
@@ -27,7 +27,7 @@
 defined('MOODLE_INTERNAL') || die;
 
 $plugin->version   = 2022060800;
-$plugin->requires  = 2016051900;
+$plugin->requires  = 2022112800;  // Require at least Moodle 4.1.0.
 $plugin->cron      = 0;
 $plugin->component = "local_listcoursefiles";
 $plugin->maturity  = MATURITY_STABLE;