Rocket Loader Magento 2.4.2


as soon I activate Rocket Loader Google PageSpeed Insight warns me:

  • Reduce the impact of third-party code Third-party code blocked the main thread for 790 ms

Transfer Size Main-Thread Blocking Time
5 KiB 791 ms

If I were to guess, it’s because Rocket Loader merges a lot of JS together, which can take longer. I don’t use it. With HTTP/2, JS should load in parallel and hopefully finish earlier.

Its improoved the Google Score by about 12 points, so it helps.
HTTP/2 is only for Edge and Chrome i thought, here 70% are using Firefox.

Firefox offered HTTP 2 and 3 long before Chrome :slight_smile:

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Cloudfare tells: User using the Safari and Edge browsers experience the most significant improvements.

Let me quickly link some other posts where is explained what it does and why it is renderblocking.

Rocket Loader native optimization.

Rocket Loader is not doing magic, to optimize and make you gain 12 points, it takes some time.

So everything comes at a price and Rocket Loader just blocks as long as it takes to optimize and restructure your DOM - The longer it takes, the more is to optimize. Rocket Loader is a really awesome add-on you can quickly activate, but the real deal is always native optimization.

So better hire a specialist in web optimization who analyses your domain setup/server setup/templates for what could be done to perform better and then implement these changes. After having optimized everything you can turn Rocket Loader off, once you perform a better GPSI score without Rocket Loader you have achieved your goal! From now on your optimization level is so high Rocket Loader can not improve your site, and you should not include it anymore as it produces render blocking.

If you run a commercial shop it will always be worth it’s doing thing right and performing better than others.

Just curious, is this mobile or desktop?

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