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ConstructFieldXpathRector

Fixes deprecated AssertLegacyTrait::constructFieldXpath() calls

-$this->constructFieldXpath('id', 'edit-preferred-admin-langcode');
+$this->getSession()->getPage()->findField('edit-preferred-admin-langcode');

Configure your rector.php:

<?php

use DrupalRector\Drupal9\Rector\Deprecation\ConstructFieldXpathRector;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withRules([
        ConstructFieldXpathRector::class,
    ]);