Issue #3296959: Drupal 10 compatibility

Closes #3296959

src/Plugin/diff/Field/TextWithSummaryFieldBuilder.php

@@ -31,11 +31,12 @@ class TextWithSummaryFieldBuilder extends FieldDiffBuilderBase {
       if ($this->configuration['compare_format'] == 1) {
         if (isset($values['format'])) {
           $controller = $this->entityTypeManager->getStorage('filter_format');
+          /** @var \Drupal\filter\Entity\FilterFormat $format */
           $format = $controller->load($values['format']);
           // The format loaded successfully.
           $label = $this->t('Format');
           if ($format != NULL) {
-            $result[$field_key][] = $label . ": " . $format->name;
+            $result[$field_key][] = $label . ": " . $format->get('name')->value;
           }
           else {
             $result[$field_key][] = $label . ": " . $this->t('Missing format @format', array('@format' => $values[$field_key]));