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Shopify fix guide

Render-Blocking JavaScript Detected on Shopify

Synchronous <script> tags in the <head> block page rendering. The browser must download and execute these scripts before painting any content.

Issue ID: CWV-RENDER-BLOCK-JS-001Severity: moderateEffort: M

Why this matters

Synchronous <script> tags in the <head> block page rendering. The browser must download and execute these scripts before painting any content. This affects load speed, Core Web Vitals, and how many visitors stay long enough to convert.

Shopify fix path

How to fix this on Shopify

Use theme settings, page settings, or theme code.

  1. 1Find the source of the issue in Shopify admin.
  2. 2Apply the change.
  3. 3Preview and publish.

After you fix it

  • Run Lighthouse and confirm no render-blocking JS warnings

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