Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires typo3/cms-core ^10.4 || ^11.5 || ^12.4 || ^13.4 -> satisfiable by typo3/cms-core[v12.4.37, v12.4.38, v12.4.39, v12.4.40, v13.4.18, v13.4.19, v13.4.20, v13.4.21]. - typo3/cms-core[v12.4.37, ..., v12.4.40, v13.4.18, ..., v13.4.21] require ext-intl * -> it is missing from your system. Install or enable PHP's intl extension. To enable extensions, verify that they are enabled in your .ini files: - /usr/local/etc/php/conf.d/docker-php-ext-sodium.ini You can also run `php --ini` in a terminal to see which files are used by PHP in CLI mode. Alternatively, you can run Composer with `--ignore-platform-req=ext-intl` to temporarily ignore these required extensions.