Tagged: perception

Good little case study on how YouTube optimized their First Contentful Paint and Largest Contentful Paint by applying preload and fetchpriority to their poster image.

My favorite nugget is that they tested using an actual video thumbnail for their poster image versus a solid black poster image, and the black image performed better in user studies:

Using a solid black poster image showed the best results in user studies. Users found the transition from solid black to the first frame of the video to be a less-jarring experience for autoplay videos.

The folks at Chrome, talking about the business impact of hitting their Core Web Vitals thresholds:

We analyzed millions of page impressions to understand how these metrics and thresholds affect users. We found that when a site meets the above thresholds, users are 24% less likely to abandon page loads (by leaving the page before it finishes loading).

We also looked specifically at news and shopping sites, sites whose businesses depend on traffic and task completion, and found similar numbers: 22% less abandonment for news sites and 24% less abandonment for shopping sites.

Super interesting insight into how the folks over at Google came up with their new Core Web Vitals—including everything from how they figured out what "good" or "poor" looked like, how they chose which percentiles to look at, and more.

Lovely performance "postmortem" from Eli Fitch about how MapBox got their first-meaningful-paint to drop from 4.7s to 1.9 seconds.

Some good insights into technical optimizations, but as always, the cultural aspects are the most difficult–and the most important.

Nurturing cultural awareness and enthusiasm for building fast, snappy, responsive, tactile products is arguably the most effective performance improvement you can make, but can be the most challenging, and requires the most ongoing attention.