How to Reduce CLS Issue on Desktop in Shopify's Dawn Theme: A Comprehensive Guide

How to Reduce CLS Issue on Desktop in Shopify's Dawn Theme: A Comprehensive Guide

Cumulative Layout Shift (CLS) is a metric that measures the visual stability of a webpage. A high CLS score can significantly impact the user experience, particularly on desktop devices. If you're struggling to reduce the CLS on desktop for your Shopify store using the Dawn theme, you've come to the right place. This detailed guide will help you understand the problem, identify its causes, and provide actionable solutions to resolve it.

Understanding Cumulative Layout Shift (CLS)

CLS measures the unexpected shifting of webpage elements during the loading phase. A low CLS score indicates a stable and smooth user experience, while a high CLS score suggests a disruptive user interface, which can affect both user satisfaction and SEO performance.

Causes of High CLS

  1. Missing Dimensions for Images and Videos: If dimensions (width and height) are not set for media elements, the browser can't allocate space for them in advance, causing shifts when they load.
  2. Late Loading of Fonts: Using web fonts that load late can cause text reflows, contributing to high CLS.
  3. Injected Content: Ads, pop-ups, and other on-page elements can inject content dynamically, causing layout shifts.
  4. Dynamic Elements: Elements like sliders, carousels, and rotating banners can lead to layout shifts if not managed properly.

Identifying the CLS Issue

Based on your PageSpeed Insights report, your desktop CLS score is at .385, which is considered high. The following issues were highlighted:

  • A late network request adjusted the page layout.
  • The CLS issue persists only on desktop and not on mobile.

To break down why these issues are happening, let's dive deeper.

Solutions to Fix CLS on Desktop

1. Set Explicit Dimensions for All Media Elements

Ensure that all images and videos have defined width and height attributes. This allows the browser to allocate the necessary space for these elements, preventing layout shifts.

<img src="your-image.jpg" width="600" height="400" alt="Description">

2. Preload Fonts

Late-loading fonts can cause text reflows. By preloading key web fonts, you can ensure they load earlier in the CSS rendering process.

<link rel="preload" href="/fonts/your-font.woff2" as="font" type="font/woff2" crossorigin="anonymous">

3. Avoid Injecting Content Dynamically

Ads, pop-ups, and other dynamically injected elements should have defined dimensions or be loaded in a manner that doesn't impact the layout.

4. Optimize Third-Party Scripts

Third-party scripts can often lead to layout shifts. Load them asynchronously or defer them to minimize their impact.

<script src="your-script.js" async></script>

5. Reserve Space for Ads and Banners

If you're using ads, ensure that you reserve space for them using CSS. This prevents the content from shifting once the ads load.

.ad-space {
   width: 300px;
   height: 250px;

6. Test with Real Users

Tools like Google Analytics and field data from Core Web Vitals can provide insights into CLS experienced by real users. Use this data to make more informed decisions.

7. Monitor and Iterate

Regularly check your site's CLS score on PageSpeed Insights or Lighthouse. Continuous monitoring ensures that any changes you make contribute positively to your page's visual stability.

Common Questions and Answers

Q: Why is my CLS higher on desktop than on mobile?

A: Desktop screens typically have more complex layouts and larger media elements. Additionally, desktop browsers might handle certain CSS differently, leading to higher CLS.

Q: Do third-party plugins impact CLS?

A: Yes, third-party plugins can inject content or load scripts that cause layout shifts. Always test and optimize these elements.

Q: Can lazy-loading images reduce CLS?

A: While lazy-loading can improve page speed, it can contribute to CLS if not implemented correctly. Ensure placeholders or defined dimensions are used.

Q: Is CLS a ranking factor for SEO?

A: Yes, CLS is part of Google's Core Web Vitals, which are important ranking factors for SEO.


Reducing CLS is crucial for providing a stable and smooth user experience on your Shopify store. By understanding the causes and implementing the solutions outlined in this guide, you can significantly improve your desktop CLS score. Remember, continuous monitoring and optimization are key to maintaining a low CLS score.

If you're struggling with these issues, don't hesitate to seek professional help. As a Shopify expert, I specialize in speed improvement and theme development. Feel free to reach out for personalized assistance.

Have a nice day!

For further queries or custom modifications to your store, feel free to email me.

If you found this helpful, please like and accept the solution. Want to buy me a coffee? [Buy Me A Coffee (Add link)]