Category: XHTML / JS / CSS

Recently, a few clients and friends reached out to me with a puzzling issue: their Shopify collection pages’ infinite scroll functionality suddenly stopped working as expected. The symptoms were consistent across different stores:

1. The problem occurs specifically on collection pages
2. The infinite scroll keeps re-appending the same “next page” content from the initial page visit, instead of loading subsequent pages properly.
   For example:
   • If a visitor lands on page 1, infinite scroll keeps appending page 2 repeatedly;
   • If a visitor lands directly on page 5, infinite scroll keeps appending page 6 repeatedly

Initial Thoughts and Investigation

At first glance, it might seem like an outdated infinite scroll plugin or a browser update causing the problem. However, two key points suggested otherwise:

1. The issue was reported by multiple merchants using different infinite scroll plugins (e.g., infinite-scroll.com)
2. All affected stores were on Shopify, not other platforms like Shopline or WooCommerce

This strongly indicated that the root cause was a recent change on Shopify’s side.

How Infinite Scroll Plugins Work and the Discovery of the phcursor Parameter

Infinite scroll plugins typically monitor pagination links on collection pages, detect URL patterns, and then fetch the next page content accordingly. While inspecting the pagination links, I noticed an unfamiliar URL parameter: phcursor.
Given the prefix ph and the word “cursor,” it’s reasonable to assume this parameter acts as a pointer or cursor for Shopify’s internal product listing queries to improve lookup performance.
Searching for phcursor led me to a Shopify developer community discussion where others reported similar problems:

https://community.shopify.dev/t/a-new-phcursor-pagination-parameter/17715

What’s happening is that Shopify now uses this new phcursor parameter to indicate the starting product of the next page. When this parameter is present, Shopify returns products starting from that cursor position, ignoring the traditional page number parameter.

The problem arises because the infinite scroll plugin inherits this phcursor parameter with every subsequent page request. As a result, the plugin keeps appending the same “next page” content repeatedly, causing an infinite loop of duplicated products.

I believe Shopify introduced this parameter to boost collection page performance. However, since it’s a newly introduced, undocumented parameter, it shouldn’t be mandatory for pagination to work correctly—especially for third-party plugins.

How to Fix the Issue

Currently, there are 2 practical approaches I can think of to resolve this:

1. Adjust Your Infinite Scroll Plugin Logic
   Modify your infinite scroll plugin’s code to explicitly ignore or remove the phcursor parameter when constructing URLs for subsequent pages. This approach is plugin-specific and may require a developer familiar with your chosen plugin;
2. Remove the phcursor Parameter from Pagination Links via JavaScript
   Since infinite scroll plugins operate in JavaScript, you can add a small script to your theme that strips out the phcursor parameter from pagination links before the infinite scroll plugin runs. This approach is more universal and doesn’t require modifying plugin code directly.

I won’t share the exact code here, as it should be tailored to your store’s theme and plugin setup. I recommend consulting a Shopify developer to implement the best solution for your site.

Final Thoughts

Shopify regularly rolls out major updates quarterly and often introduces subtle changes in between. While these improvements—like the phcursor parameter—aim to enhance performance and user experience, unannounced changes that inadvertently break common third-party features can be frustrating for merchants and developers alike.

I hope Shopify will consider providing earlier announcements or documentation when introducing such changes to help merchants and developers adapt smoothly.

If your store is experiencing this infinite scroll issue, feel free to reach out. I offer affordable freelance support to help you implement the necessary fixes quickly and efficiently.

Thank you for reading! Let’s keep Shopify stores running smoothly together.

Supplementary

9 Jul 2025:
2 days after I wrote this blog, I found an article wrote by Shopify Engineer on 12 Aug, 2019:
https://shopify.engineering/pagination-relative-cursors

This further confirms my guess that Shopify is rolling out changes to improve Collection page performance.

Further reading

• Understanding the Offset and Cursor Pagination
• 龐大資料庫分頁方案 Cursor-based pagination
• Cursor pagination: how it works and its pros and cons