Shopify Product Review app is loading slow

Technical Q&A

Topic summary

Product Reviews widget displays noticeably after the rest of the product page because it’s injected via third‑party scripts that load after main HTML/CSS. This slight delay is common across review apps; some alternatives may load faster.

SEO impact: Overall site performance influences SEO. While you may not eliminate the delay, you can improve page performance by adjusting script loading. Using async (load in parallel) or defer (load after parsing) can reduce blocking; for review widgets, defer was suggested as preferable.

Implementation details: The widget appears via a div, while the actual script isn’t in theme.liquid because Shopify adds it through the ScriptTag resource (an admin-level injector for external scripts). You can confirm scripts at /admin/script_tags.json. Direct edits may not be possible.

Optimizations and actions:

  • Only load the reviews script on product pages using conditional Liquid.
  • Verify current loading (Shopify’s widget appears to already load async) and contact the app’s support for further optimization.
  • Consider other review apps if speed is critical.

Newest update: A participant observed scripts may load only after user interaction (e.g., mouse movement), which could affect perceived load timing; this behavior needs further investigation.

Status: No definitive fix; discussion remains open with suggested workarounds and checks.

Summarized with AI on January 29. AI used: gpt-5.
7

Hi @dennisve ,

Site speed does affect SEO performance. But there isn’t so much that can be done to optimize third party scripts although you could implement @JohnCodes defer solution ( with the reviews it would be better to use defer than async) or load the third party scripts only on the page they are used on for example if you only use the app on the product page you shouldn’t load the app scripts on every page (adding something like below within your tag should work).

{% if request.page_type == "product" %} 

{% endif %}

However, there are likely other things on your site that can be improved to optimize your sites performance. If you can provide your website url we can have a look?

eStoreSpeedOptimization