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Configurable

ReplaceRebuildThemeDataRector

Replaces removed ThemeHandlerInterface::rebuildThemeData() with \Drupal::service('extension.list.theme')->reset()->getList()

-$this->themeHandler->rebuildThemeData();
+\Drupal::service('extension.list.theme')->reset()->getList();

Configure your rector.php:

<?php

use DrupalRector\Drupal10\Rector\Deprecation\ReplaceRebuildThemeDataRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(ReplaceRebuildThemeDataRector::class, [
        new DrupalIntroducedVersionConfiguration('10.3.0'),
    ]);