diff --git a/customfield/classes/api.php b/customfield/classes/api.php
index 6ebce70d304..08e744ae4dc 100644
--- a/customfield/classes/api.php
+++ b/customfield/classes/api.php
@@ -254,7 +254,7 @@ class api {
                                     $category->get_formatted_name(),
                                     $category->get('name'),
                                     get_string('editcategoryname', 'core_customfield'),
-                                    get_string('newvaluefor', 'core_form', format_string($category->get('name')))
+                                    get_string('newvaluefor', 'core_form', $category->get_formatted_name())
         );
     }
 
diff --git a/customfield/classes/handler.php b/customfield/classes/handler.php
index de75119aea0..1a44127854d 100644
--- a/customfield/classes/handler.php
+++ b/customfield/classes/handler.php
@@ -638,7 +638,7 @@ abstract class handler {
         foreach ($fieldswithdata as $data) {
             $categoryid = $data->get_field()->get_category()->get('id');
             if ($categoryid != $lastcategoryid) {
-                $categoryname = format_string($data->get_field()->get_category()->get('name'));
+                $categoryname = $data->get_field()->get_category()->get_formatted_name();
 
                 // Load category header lang string if specified.
                 if (!empty($headerlangidentifier)) {
diff --git a/customfield/lib.php b/customfield/lib.php
index 0c3986d6406..f9aab27eabd 100644
--- a/customfield/lib.php
+++ b/customfield/lib.php
@@ -42,7 +42,7 @@ function core_customfield_inplace_editable($itemtype, $itemid, $newvalue) {
         if (!$handler->can_configure()) {
             throw new moodle_exception('nopermissionconfigure', 'core_customfield');
         }
-        $newvalue = clean_param($newvalue, PARAM_NOTAGS);
+        $newvalue = clean_param($newvalue, PARAM_TEXT);
         $handler->rename_category($category, $newvalue);
         return \core_customfield\api::get_category_inplace_editable($category, true);
     }
diff --git a/customfield/upgrade.txt b/customfield/upgrade.txt
index ae20f2d948f..73d2537a7ab 100644
--- a/customfield/upgrade.txt
+++ b/customfield/upgrade.txt
@@ -1,6 +1,10 @@
 This files describes API changes in /customfield/*,
 Information provided here is intended especially for developers.
 
+=== 4.3 ===
+* Field categories are now consistently of type `PARAM_TEXT`, ensure instance `get_formatted_name()` helper is used
+  during output
+
 === 4.2 ===
 * The `\customfield_select\field_controller::get_options_array` method, deprecated since 3.10, has been removed, use
   the field instance `get_options` method instead