We’ve upgraded GTmetrix to Lighthouse 7.4.0 and Chrome 90 – read on for changes that come with this release.

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Lighthouse 7.4.0

Moving from Lighthouse 6.3.0 to 7.4.0 saw mostly internal changes that wouldn’t affect GTmetrix users. The most notable changes are three new audits now available in GTmetrix:
 

• Preload Largest Contentful Paint image
  • Checks if an image in your LCP element is preloaded.
     
• Lazy load third-party resources with facades
  • Detects if third-party media/content embeds are present and recommends substitution with a “facade” to expedite page load.
     
• Use explicit width and height on image elements
  • Checks if images have proper width and height defined to ensure minimal layout shift.
     

While these new audits have relatively low impacts to your Structure score, they are relatively simple to resolve, and can offer overall page performance improvements if applied correctly.
 

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Chrome 90

There have been a few LCP and CLS definition changes since our last version of Chrome (v86), which should generally fix some edge cases with certain pages.

• LCP Definition Improvements
  • Read official Chrome documentation
     
• CLS Definition Improvements
  • Read official Chrome documentation
     

Overall, new LCP and CLS definition changes aim to reflect more real-world behaviour with regards to page load performance.

 

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General updates and improvements

More changes in this release:
 

• Removed “Replace large JavaScript libraries with smaller alternatives” audit
  • Moved to “experimental” in Lighthouse 6.4.0
     
• Modified audit titles
  • “Remove unused CSS” is now “Reduce unused CSS”
  • “Remove unused JavaScript” is now “Reduce unused JavaScript”
     
• Removed mention of HTTP2 Push
  • Changed in Lighthouse 7.0.0
     
• Cached reports for curbing abuse
  • A cached report will be served if a page is tested more than 5 times within 5 minutes.
  • Users must log in to continue testing.
     
• Fixed URL block/allow bug
  • URL block/allow was not working in certain situations with iframes
     
• Added the following CDNs for auto-detection:
  • Nexcess CDN
  • NOC.org

 

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Let us know if you run across any bugs or issues and feel free to tell us your thoughts on Twitter (@gtmetrix) or contact us.

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