Joseph Scott
@josephscott.bsky.social
Reposted by Joseph Scott
#LCP and #INP support in #Safari really coming close now (maybe even in 2025?) as Safari 26.2 Beta Release Notes includes:
- support for the Event Timing API
- Largest Contentful Paint metric
Great work by the #Webkit team!
A blogpost:
www.rumvision.com/blog/safari-...
- support for the Event Timing API
- Largest Contentful Paint metric
Great work by the #Webkit team!
A blogpost:
www.rumvision.com/blog/safari-...
Safari catching up: INP and LCP support in the same beta release
Real User Monitoring
www.rumvision.com
November 5, 2025 at 10:35 AM
#LCP and #INP support in #Safari really coming close now (maybe even in 2025?) as Safari 26.2 Beta Release Notes includes:
- support for the Event Timing API
- Largest Contentful Paint metric
Great work by the #Webkit team!
A blogpost:
www.rumvision.com/blog/safari-...
- support for the Event Timing API
- Largest Contentful Paint metric
Great work by the #Webkit team!
A blogpost:
www.rumvision.com/blog/safari-...
Realizing now that for my #webperf folks I should have dressed up in the scariest of all possible Halloween costume: your p99 metric value
November 5, 2025 at 3:19 PM
Realizing now that for my #webperf folks I should have dressed up in the scariest of all possible Halloween costume: your p99 metric value
Do future you ( and others ) a favor - check your return values. Funny how something that was an edge case that "never happens" at some point in the future starts happening every day.
November 3, 2025 at 2:39 PM
Do future you ( and others ) a favor - check your return values. Funny how something that was an edge case that "never happens" at some point in the future starts happening every day.
Reposted by Joseph Scott
Using the new WPT UI that @catchpointsystems.bsky.social just rolled out, and I'm angry and sad and frustrated and deeply confused all at once. What an utter debacle. Roll this back.
October 24, 2025 at 4:47 PM
Using the new WPT UI that @catchpointsystems.bsky.social just rolled out, and I'm angry and sad and frustrated and deeply confused all at once. What an utter debacle. Roll this back.
Reposted by Joseph Scott
Tomorrow we lose access to the current version of WebPageTest and will be forced into the new version. I’m dreading the switch. Experiments are a HUGE step backwards and I use them all the time. The interface may be consistent with Catchpoint UI, but it is boring and confusing if all you use is WPT.
October 22, 2025 at 8:46 PM
Tomorrow we lose access to the current version of WebPageTest and will be forced into the new version. I’m dreading the switch. Experiments are a HUGE step backwards and I use them all the time. The interface may be consistent with Catchpoint UI, but it is boring and confusing if all you use is WPT.
Login flows that require me to bounce back to email are way more annoying than the traditional username/password.
October 22, 2025 at 2:51 PM
Login flows that require me to bounce back to email are way more annoying than the traditional username/password.
Injecting an automated blurred preview at the beginning of an image file is an interesting approach. At some point, if you can get the blurred preview down to a small enough size it seems worthwhile to just include in the image itself.
I dug into progressive image rendering and found a bunch of common assumptions aren't quite true.
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...
The present and potential future of progressive image rendering
Exploring progressive image rendering across JPEG, PNG, WebP, AVIF, and JPEG XL.
jakearchibald.com
October 16, 2025 at 5:37 PM
Injecting an automated blurred preview at the beginning of an image file is an interesting approach. At some point, if you can get the blurred preview down to a small enough size it seems worthwhile to just include in the image itself.
I suspect INP and LCP in Safari is going to be a real eye opener. Looking forward to more perf data from all those iPhone users.
I spy with my little eye both INP and LCP enabled by default in the latest Safari Tech Preview.
What with Firefox landing INP in stable yesterday (on top of LCP that they already supported) this means we'll soon have cross-browser support for these two Core Web Vitals!
#interop2025 #CoreWebVitals
What with Firefox landing INP in stable yesterday (on top of LCP that they already supported) this means we'll soon have cross-browser support for these two Core Web Vitals!
#interop2025 #CoreWebVitals
October 15, 2025 at 10:32 PM
I suspect INP and LCP in Safari is going to be a real eye opener. Looking forward to more perf data from all those iPhone users.
Wait, Tron: Legacy was 15 years ago? It is official, my sense of time is unreliable.
October 7, 2025 at 3:54 PM
Wait, Tron: Legacy was 15 years ago? It is official, my sense of time is unreliable.
To everyone who insist on breaking the ability to paste into forms on the web - stop it.
October 1, 2025 at 5:45 PM
To everyone who insist on breaking the ability to paste into forms on the web - stop it.
Reposted by Joseph Scott
🚨 New tool: Impolighthouse
Not just “how fast is my site?”, but “why is it slow, and what does that say about our org?”
A deliberately impolite wrapper on top of Lighthouse, that calls out your organizational cruft, blockers & bad decisions.
www.jonoalderson.com/impolighthou...
Not just “how fast is my site?”, but “why is it slow, and what does that say about our org?”
A deliberately impolite wrapper on top of Lighthouse, that calls out your organizational cruft, blockers & bad decisions.
www.jonoalderson.com/impolighthou...
Impolighthouse
Get brutally honest performance feedback that actually tells you what's wrong and how to fix it.
www.jonoalderson.com
September 23, 2025 at 10:53 AM
🚨 New tool: Impolighthouse
Not just “how fast is my site?”, but “why is it slow, and what does that say about our org?”
A deliberately impolite wrapper on top of Lighthouse, that calls out your organizational cruft, blockers & bad decisions.
www.jonoalderson.com/impolighthou...
Not just “how fast is my site?”, but “why is it slow, and what does that say about our org?”
A deliberately impolite wrapper on top of Lighthouse, that calls out your organizational cruft, blockers & bad decisions.
www.jonoalderson.com/impolighthou...
Reposted by Joseph Scott
forgot to put this up somewhere so here you go. visualize your favorite zlib stream! lynn.github.io/flateview/
September 21, 2025 at 10:56 AM
forgot to put this up somewhere so here you go. visualize your favorite zlib stream! lynn.github.io/flateview/
I'd like to see fetchLater make into the Interop work github.com/web-platform...
fetchLater API · Issue #1069 · web-platform-tests/interop
Description fetchLater() is a Fetch API that lets pages queue a deferred network request the browser will send later (when the document is destroyed, after a specified timeout, or at a UA-chosen ti...
github.com
September 12, 2025 at 3:04 PM
I'd like to see fetchLater make into the Interop work github.com/web-platform...
Do you have hundreds of thousands of posts in WordPress? This new index will help speed up the admin user view of the `All Posts` page in wp-admin - core.trac.wordpress.org/changeset/60... - for background and data see core.trac.wordpress.org/ticket/50161... #wordpress #mysql #webperf
Changeset 60717 – WordPress Trac
Blog Tool and Publishing Platform
core.trac.wordpress.org
September 8, 2025 at 7:10 PM
Do you have hundreds of thousands of posts in WordPress? This new index will help speed up the admin user view of the `All Posts` page in wp-admin - core.trac.wordpress.org/changeset/60... - for background and data see core.trac.wordpress.org/ticket/50161... #wordpress #mysql #webperf
It has been ten years since Choose Boring Technology was published - mcfunley.com/choose-borin... - good time to remind you about the concept of `innovation tokens`. Too often we spend all three at once, plus a few more we tried to borrow from our future selves. #boringtech
September 4, 2025 at 3:56 PM
It has been ten years since Choose Boring Technology was published - mcfunley.com/choose-borin... - good time to remind you about the concept of `innovation tokens`. Too often we spend all three at once, plus a few more we tried to borrow from our future selves. #boringtech
Everything is a trade off - which means someone has to make a decision.
September 4, 2025 at 2:04 PM
Everything is a trade off - which means someone has to make a decision.
“Luck is what happens when preparation meets opportunity.” - Seneca
September 2, 2025 at 9:33 PM
“Luck is what happens when preparation meets opportunity.” - Seneca
Reposted by Joseph Scott
Periodic reminder: a brand new DOM on top of canvas is an idea that floats every so often and would not work. The edge cases already baked into HTML are vast and reproducing all of them in a shiny new thing is futile.
We can't go over it, we can't go under it, we've got to go through it.
We can't go over it, we can't go under it, we've got to go through it.
August 13, 2025 at 11:42 AM
Periodic reminder: a brand new DOM on top of canvas is an idea that floats every so often and would not work. The edge cases already baked into HTML are vast and reproducing all of them in a shiny new thing is futile.
We can't go over it, we can't go under it, we've got to go through it.
We can't go over it, we can't go under it, we've got to go through it.
🤯 I have been a developer for 17 years. I only learned this YESTERDAY.
www.youtube.com/watch?v=81JU...
www.youtube.com/watch?v=81JU...
Better DevTools Workflows With //# sourceURL
YouTube video by Harry Roberts
www.youtube.com
August 11, 2025 at 3:16 PM
There is a PR to add the SPX profiler extension to wp-env github.com/WordPress/gu... which would make it easier to do performance analysis, I'm hoping this will get merged. If you haven't tried SPX yet, it is worth a look - github.com/NoiseByNorth... #wordpress #spx #performance
Add wp-env SPX profiler option by nerrad · Pull Request #70693 · WordPress/gutenberg
What?
Implements SPX (Simple Profiling eXtension) support in the @wordpress/env package, providing lightweight PHP profiling capabilities with a built-in web UI.
Why?
SPX offers a more lightweight ...
github.com
August 4, 2025 at 4:49 PM
There is a PR to add the SPX profiler extension to wp-env github.com/WordPress/gu... which would make it easier to do performance analysis, I'm hoping this will get merged. If you haven't tried SPX yet, it is worth a look - github.com/NoiseByNorth... #wordpress #spx #performance
Not excited about this new /tmp default in Debian 13 Trixie to use tmpfs - www.debian.org/releases/tri... - I'd rather default to cheaper disk space than more limited and expensive memory #debian
5. Issues to be aware of for trixie — release-notes documentation
www.debian.org
July 23, 2025 at 4:04 PM
Not excited about this new /tmp default in Debian 13 Trixie to use tmpfs - www.debian.org/releases/tri... - I'd rather default to cheaper disk space than more limited and expensive memory #debian