diff --git a/core/lib/Drupal/Core/Field/WidgetBase.php b/core/lib/Drupal/Core/Field/WidgetBase.php
index 4da8a54edf..cfc2478f83 100644
--- a/core/lib/Drupal/Core/Field/WidgetBase.php
+++ b/core/lib/Drupal/Core/Field/WidgetBase.php
@@ -120,7 +120,7 @@ public function form(FieldItemListInterface $items, array &$form, FormStateInter
     // Populate the 'array_parents' information in $form_state->get('field')
     // after the form is built, so that we catch changes in the form structure
     // performed in alter() hooks.
-    $elements['#after_build'][] = [get_class($this), 'afterBuild'];
+    $elements['#after_build'][] = [static::class, 'afterBuild'];
     $elements['#field_name'] = $field_name;
     $elements['#field_parents'] = $parents;
     // Enforce the structure of submitted values.
@@ -225,13 +225,13 @@ protected function formMultipleElements(FieldItemListInterface $items, array &$f
               '#type' => 'submit',
               '#value' => t('Remove'),
               '#validate' => [],
-              '#submit' => [[get_class($this), 'submitRemove']],
+              '#submit' => [[static::class, 'submitRemove']],
               '#limit_validation_errors' => [],
               '#attributes' => [
                 'class' => ['remove-field-delta--' . $delta],
               ],
               '#ajax' => [
-                'callback' => [get_class($this), 'removeAjaxContentRefresh'],
+                'callback' => [static::class, 'removeAjaxContentRefresh'],
                 'wrapper' => $wrapper_id,
                 'effect' => 'fade',
               ],
@@ -267,9 +267,9 @@ protected function formMultipleElements(FieldItemListInterface $items, array &$f
         '#value' => $delta > 0 ? t('Add another item') : t('Add item'),
         '#attributes' => ['class' => ['field-add-more-submit']],
         '#limit_validation_errors' => [],
-        '#submit' => [[get_class($this), 'addMoreSubmit']],
+        '#submit' => [[static::class, 'addMoreSubmit']],
         '#ajax' => [
-          'callback' => [get_class($this), 'addMoreAjax'],
+          'callback' => [static::class, 'addMoreAjax'],
           'wrapper' => $wrapper_id,
           'effect' => 'fade',
         ],