Version 1.11.0+
Preloading can be a useful way of making sure that critical assets are downloaded by the browser as soon as possible for better rendering performance.
Liquid provides multiple filters to preload key resources so they can be converted into Link headers automatically. This enables them to be discovered even faster, especially when combined with Early Hints that Shopify supports.
The following examples contain code snippets that either fail or pass this check.
<link href="{{ 'script.js' | asset_url }}" rel="preload" as="script">
<link href="{{ 'style.css' | asset_url }}" rel="preload" as="style">
<link href="{{ 'image.png' | asset_url }}" rel="preload" as="image">{{ 'script.js' | asset_url | preload_tag: as: 'script' }}
{{ 'style.css' | asset_url | stylesheet_tag: preload: true }}
{{
product.featured_image
| image_url: width: 600
| image_tag: preload: true
}}The following example contains the default configuration for this check:
AssetPreload:
enabled: true
severity: suggestion| Parameter | Description |
|---|---|
| enabled | Whether the check is enabled. |
| severity | The severity of the check. |
It's safe to disable this rule. You may want to do it when trying to preload assets from external domain and it is not possible to move them to Shopify because they change frequently or are dynamically generated.