Shopify fix guide
Long Main Thread Tasks Detected on Shopify
JavaScript tasks exceeding 50ms block the main thread, causing jank and poor responsiveness. This directly impacts INP and user experience.
Issue ID: CWV-LONG-TASKS-001Severity: majorEffort: L
Why this matters
JavaScript tasks exceeding 50ms block the main thread, causing jank and poor responsiveness. This directly impacts INP and user experience. 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.
- 1Find the source of the issue in Shopify admin.
- 2Apply the change.
- 3Preview and publish.
After you fix it
- ✓Use Chrome DevTools Performance panel to confirm no tasks exceed 50ms
Same fix, other platforms
Fix long main thread tasks detected on a different CMS
Other fixes
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