How can I remove unused code after uninstalling apps?

Shopify Discussion

Topic summary

Core Issue:
Shopify store owners struggle with leftover code from uninstalled apps that slows page speed. No automated app exists to clean this code.

Key Findings & Solutions:

  • Shopify’s New Requirements: As of ~2 months ago, Shopify requires apps to provide automatic code removal upon uninstallation. Users should reinstall apps briefly to check for cleanup buttons.

  • Diagnostic Approach: Use Chrome DevTools (right-click → Inspect → Network tab) to identify slow-loading resources and trace them to specific apps or theme files.

  • Common Culprits:

    • Facebook Pixel requests (often duplicated, sometimes 3+ instances)
    • Review apps (Ali Reviews, Judge.me, Yotpo, Opinew)
    • Loyalty/rewards programs
    • Chat widgets and email marketing tools
    • Unused CSS/JavaScript from themes

  • Recommended Actions:

    1. Contact app developers for optimization help
    2. Add loading="lazy" to image tags for lazy loading
    3. Search theme files for app references using text editors
    4. Consolidate duplicate pixels/tracking codes
    5. Remove unused apps completely following developer uninstall guides

Important Caveats:

  • Some JavaScript loads after main page (via Shopify script tags), so doesn’t actually slow initial load despite Google reports
  • Theme core files shouldn’t be modified without expertise
  • Google Lighthouse scores simulate slow connections and may not reflect real user experience
  • Professional developer help recommended for complex code removal
Summarized with AI on October 31. AI used: claude-sonnet-4-5-20250929.
142

Hi Oli,

I’ve noticed that you’re helping a lot of people with their Shopify speeds. I’m struggling with my store speed as well - Lighthouse is showing a score of 31 which seems extremely low. Apparently it’s due to some unused JS “cdn.shopify.com/vendor…”, but I have no idea what to do with it. Any chance you could tell me what to do to optimise it? :slightly_smiling_face:

The store address is nutreally.co

Cheers!