diff --git a/lib/classes/string_manager_standard.php b/lib/classes/string_manager_standard.php
index dbcfdcf131e..6d4f8595de7 100644
--- a/lib/classes/string_manager_standard.php
+++ b/lib/classes/string_manager_standard.php
@@ -363,7 +363,7 @@ class core_string_manager_standard implements core_string_manager {
 
         if ($a !== null) {
             // Process array's and objects (except lang_strings).
-            if (is_array($a) or (is_object($a) && !($a instanceof lang_string))) {
+            if (is_array($a) or (is_object($a) && !($a instanceof Stringable))) {
                 $a = (array)$a;
                 $search = array();
                 $replace = array();
@@ -372,7 +372,7 @@ class core_string_manager_standard implements core_string_manager {
                         // We do not support numeric keys - sorry!
                         continue;
                     }
-                    if (is_array($value) or (is_object($value) && !($value instanceof lang_string))) {
+                    if (is_array($value) or (is_object($value) && !($value instanceof Stringable))) {
                         // We support just string or lang_string as value.
                         continue;
                     }
diff --git a/lib/classes/task/send_login_notifications.php b/lib/classes/task/send_login_notifications.php
index 245a518fb5a..e32cf28d06a 100644
--- a/lib/classes/task/send_login_notifications.php
+++ b/lib/classes/task/send_login_notifications.php
@@ -61,7 +61,7 @@ class send_login_notifications extends adhoc_task {
         $userauth = get_auth_plugin($USER->auth);
         if ($userauth->can_change_password()) {
             if ($changepwurl = $userauth->change_password_url()) {
-                $changepasswordlink = (string) $changepwurl;
+                $changepasswordlink = $changepwurl;
             } else {
                 $changepasswordlink = (new \moodle_url('/login/change_password.php'))->out(false);
             }
diff --git a/lib/upgrade.txt b/lib/upgrade.txt
index 24275360fc3..739edb2fc5b 100644
--- a/lib/upgrade.txt
+++ b/lib/upgrade.txt
@@ -5,6 +5,8 @@ information provided here is intended especially for developers.
 
 * Admin settings for passwords (admin_setting_configpasswordunmask) can now be a required field using the following class:
     - admin_setting_requiredpasswordunmask
+* The `$a` argument passed to `get_string` can now include any stringable type, removing the need for explicit casts (for
+  example, of `\moodle_url` instances)
 * The badges_get_oauth2_service_options() method has been deprecated, because it's not required anymore. It should no longer
   be used.
 * Support for the following phpunit coverage info properties, deprecated since 3.11, has been removed: