Spade shape with cobalt blue background

Performance Newsletter

Archives
Calibre Monitoring
Free Speed Tools
Log in
Subscribe
11 April 2023

⚡ 124: What happens when JavaScript fails

͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏ ͏
 
Performance Newsletter
[issue 124]()
 
#### Editor’s note
 
Here I am on a long, public holiday weekend in Australia, relaxing on the couch and browsing the Internet on my phone. See, this used to be at least a semi-pleasant activity. Now, I’m either bombarded by popups, clicking random links (because the content is constantly shifting), or abandoning my leisurely browsing altogether because whatever website I was on has crashed or hung into the spiral of overlapping loaders.

When I got the Internet, this is not how I hoped it would turn out. At some point, we’ve collectively given into the idea that JavaScript has to be necessary and *the* way to serve *all* sorts of content. We abandoned progressive enhancement. And the Web is worse for it.

It’s heartening to see movement to reclaim a more stable, reliable and calmer web. I hope we get there.

 
Karolina
 
 
 
 
#### What’s Performance newsletter?
 

Performance Newsletter is a fortnightly mailing by [Calibre](https://calibreapp.com), featuring web performance tools, talks and resources.

Don’t worry—we don’t spam. If you’d like to leave, [unsubscribe]() at any time. Suggest content [here](mailto:[email protected]).

 
 
 
# Articles  
 
Emojis changing from happy to angry face
 
### [When JavaScript fails](https://scribe.rip/@jason.godesky/when-javascript-fails-52eef47e90db)
 
[Jason Godesky](https://medium.com/@jason.godesky)
JavaScript fails more often than you think, and even more so, not for the visitors who choose to turn it off entirely. What’s the cost of overreliance on JS, and how can we do better?
 
Code example of Srit component
 
### [Creating optimized responsive image tags with Svelte](https://medium.com/mkdir-awesome/creating-optimized-responsive-image-tags-with-svelte-3f282fab777b)
 
[Shinichi Okada](https://blog.codewithshin.com/about)
Using the picture element can be complex to manage. Find out how to generate responsive images easily with Srit (Svelte Responsive Image Tags).
 
### [Defaulting on Single Page Applications (SPA)](https://www.zachleat.com/web/single-page-applications/)
 
[Zach Leatherman](https://www.zachleat.com/)
Everything seems to be a SPA these days, even simple content-based websites. Does it have to be this way, especially when SPAs come with serious performance ramifications?
 
 
 
# Case Studies  
 
Code example showing a few console.time logs with timings
 
### [Making Tanstack Table 1000x faster with a 1 line change](https://jpcamara.com/2023/03/07/making-tanstack-table.html)
 
[JP Camara](https://jpcamara.com/)
Step through inspecting TanStack Table’s code, finding and addressing a performance issue that, in some cases, could have added a 30-40 second overheads.
 
 
 
# Browsers  
 
### [Largest Contentful Paint change in Chrome 112 to ignore low-entropy images](https://chromium.googlesource.com/chromium/src/+/refs/heads/main/docs/speed/metrics_changelog/2023_04_lcp.md)
 
Heads up: Chrome will now ignore images with low content relative to their display size when searching for the Largest Contentful Paint candidate. This change might affect your metrics.
 
 
 
# Courses, Talks & Podcasts  
 
Screen saying "How much FOUT affects CLS? It depends"
 
### [Reducing Layout Shifts with Custom Fallback Fonts](https://www.youtube.com/watch?v=0bZMVqXpAGY&ab_channel=HHWebPerformanceMeetup)
 
[Brian Louis Ramirez](https://screenspan.net/)
Webfonts: perceived as an expression of brand and an element that makes websites more visually pleasing. What if they cause speed headaches? Learn how to avoid drastic layout shifts when using them.
 
 
Calibre
 
This email is brought to you by the team at [Calibre](https://calibreapp.com). We automate web performance testing, reporting and alerting, so you don’t have to.
 
 

Performance Newsletter is sent from the traditional lands of the Wurundjeri people of the Kulin nation. We acknowledge that sovereignty was never ceded and pay respects to the Elders past, present and emerging.

Send your suggestions, links and feedback to [[email protected]](mailto:[email protected]).

[View or share this email →]()
[Quickly unsubscribe →]()
[Browse older issues →]()

**Sent by**
<a style='border-collapse: collapse;mso-line-height-rule: exactly;font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";text-decoration: none;font-weight: normal;margin: 0;padding: 0;mso-effects-shadow-color: #2B2B2B;color: #ffffff;'>Calibre Analytics<br/><br/>V119 / 425 Smith Street<br/>Ngár-go<br/>Fitzroy VIC 3065<br/>Australia</a>

 
Don't miss what's next. Subscribe to Performance Newsletter:
← Newer ⚡ 125: How can we build a calmer web? Older → ⚡ 123: Ultimate guide to image performance
perf.email
Bluesky
LinkedIn