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Configurable

ReplaceSystemPerformanceGzipKeyRector

Replace deprecated system.performance css.gzip/js.gzip config keys with css.compress/js.compress

-\Drupal::config('system.performance')->get('css.gzip');
+\Drupal::config('system.performance')->get('css.compress');

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\ReplaceSystemPerformanceGzipKeyRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(ReplaceSystemPerformanceGzipKeyRector::class, [
        new DrupalIntroducedVersionConfiguration('11.4.0'),
    ]);