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.
149

Hi @mjfitness ,

You have some images not using ‘lazy loading’, check back through this thread for instructions on implementing this.

The rest doesn’t look too bad, only your stylesheet is listed in ‘render-blocking resources’, so no real work to do there.

The ‘remove unused Javascript’ section of Google’s report contains the below requests. This isn’t really as important as the ‘render-blocking resources’, but you can look into them if you would really like to improve your score

Show 3rd-party resources (9)

URLTransfer SizePotential Savings


…lcpwa/bundle.js?shop=mjfitness-store.myshopify.com
(mjfitness-store.myshopify.com)
355.3 KiB
205.1 KiB

/install_assets/bold.multicurrency.js
(mc.boldapps.net)
165 KiB
93.6 KiB

…assets/vendor.js?v=593…
(cdn.shopify.com)
137 KiB
61.1 KiB

…shopify/magisto.js?shop=mjfitness-store.myshopify.com
(www.magisto.com)
80.1 KiB
49.8 KiB

/script?app=trust_badge&shop=mjfitness-store.myshopify.com
(trust.conversionbear.com)
139.8 KiB
48.2 KiB

…assets/theme.js?v=454…
(cdn.shopify.com)
51.4 KiB
36.3 KiB

/script?app=currency&shop=mjfitness-store.myshopify.com
(currency.conversionbear.com)
96.9 KiB
34.1 KiB

…1.10.2/jquery.min.js
(ajax.googleapis.com)
34.8 KiB
22.9 KiB

…boomerang/shopify-boomerang-1.0.0.min.js
(cdn.shopify.com)
54.7 KiB
20.1 KiB

Cheers,

Oli

——————————

Founder [email removed] www.preproduct.io

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