addTagsToSourceEditing example

if ($enabling_message_content) {
        $this->logger->info('The CKEditor 5 migration enabled the following plugins to support tags that are allowed by the %text_format text format: %enabling_message_content. The text format must be saved to make these changes active.',
          [
            '%text_format' => $editor->getFilterFormat()->get('name'),
            '%enabling_message_content' => $enabling_message_content,
          ]
        );
      }

      // Warn user about unsupported tags.       if (!$unsupported->allowsNothing()) {
        $this->addTagsToSourceEditing($editor, $unsupported);
        $source_editing_additions = $source_editing_additions->merge($unsupported);
        $this->logger->info("The following tags were permitted by the %text_format text format's filter configuration, but no plugin was available that supports them. To ensure the tags remain supported by this text format, the following were added to the Source Editing plugin's <em>Manually editable HTML tags</em>: @unsupported_string. The text format must be saved to make these changes active.", [
          '%text_format' => $editor->getFilterFormat()->get('name'),
          '@unsupported_string' => $unsupported->toFilterHtmlAllowedTagsString(),
        ]);
      }

      if ($enabled_for_attributes_message_content) {
        $this->logger->info('The CKEditor 5 migration process enabled the following plugins to support specific attributes that are allowed by the %text_format text format: %enabled_for_attributes_message_content.',
          [
            '%text_format' => $editor->getFilterFormat()->get('name'),