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FileUrlTransformRelativeRector

Fixes deprecated file_url_transform_relative() calls

-file_url_transform_relative($uri);
+\Drupal::service('file_url_generator')->transformRelative($uri);

Configure your rector.php:

<?php

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

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