Magento 2.4.8 Migration: Experience Feedback, Pitfalls to Avoid, and Technical Advice

Migrating to Magento 2.4.8 is not just a formality, even for seasoned platform users. Here’s a detailed experience feedback, with a healthy dose of pragmatism (and a touch of humor), to help you avoid classic pitfalls and make the most of this version’s new features.

Read the official release note (and no, don’t just ask your Magento buddy)

Before rushing headlong into migration, take the time to read the official Magento 2.4.8 release note
No, this is not the time to ask a colleague or settle for a summary on Slack: the release note is the only reliable source for identifying changes that might break your custom developments.
Each version brings its share of removed dependencies, library updates (e.g., league/flysystem, wikimedia/less.php, etc.), or behavioral changes that can cause subtle errors in your custom modules or themes
Take the time to identify:

  • Dependencies that have been removed or replaced (e.g., laminas/mime replaced by symfony/mime for attachment management).
  • Library upgrades that might impact your overrides or plugins.
  • Any breaking changes to APIs or the front end.

Update third-party modules and your theme (and discover the joys of poorly managed composer.json files)

Migration is also the perfect time to clean up your third-party modules and your theme.

  • List all installed modules and check their compatibility with Magento 2.4.8 and PHP 8.3/8.4
  • Contact vendors to get the latest versions: many modules don’t manage their composer.json properly, which can cause silent errors (Composer doesn’t complain, but the module crashes in production…).
  • Real-life example: a paid module didn’t anticipate the removal of laminas/mime and no longer handles attachments. You now have to use symfony/mime
  • Don’t forget the theme: solutions like BreezeFront often evolve faster than Magento itself. Update them regularly, without waiting for a new Magento release, to stay up to date on security and compatibility

The technical updates that sting (or save your life)

  • PHP-FTP extension required: For composer require to work with Magento 2.4.8, you now need the PHP-FTP extension. Make sure to add it to your Docker images, CI/CD, and all environments (local, preprod, prod). Otherwise, you’re guaranteed to get errors at the worst possible time
  • Service recommendations: Magento recommends migrating to Valkey (replacing Redis), updating ElasticSearch, and using MariaDB 11.4 and PHP 8.4. The good news: 2.4.8 still works with previous versions, so you can migrate Magento first, then the services. But for security and performance, don’t wait too long
  • LESS engine upgrade: The LESS engine has been upgraded, which breaks some front-end syntax. For example, the 1/@px notation no longer works; you must write (1/@px). This change aligns with recent LESS standards but can break your custom themes. Review all your .less files to avoid CSS surprises in production

Why upgrade to Magento 2.4.8

Migrating to Magento 2.4.8 is much more than a simple version bump: it’s a chance to secure your stack, anticipate security issues, take advantage of the latest performance optimizations, and ensure compatibility across your e-commerce ecosystem. Don’t skip any steps: read the release note, test your modules, update your services, and always keep an eye on front-end breaking changes. Your Magento (and your clients) will thank you!