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🎨 I gotta say, my latest is a little treasure trove: what even is `contain`?! csswizardry.com/2026/04/what...

csswizardry.comWhat Is CSS Containment and How Can I Use It? – CSS WizardryCSS containment lets you isolate layout and paint work to self-contained ‘islands’. Here’s what each contain value does and how to use it safely.

Nico Prat

@nicooprat.com

3 Apr

Nice! Tried on my app but it's hard to test if it's really effective. Using Chrome performances traces don't give consistent results run after run. How do you make sure changes are related to new styles? Thanks

Harry Roberts

@csswizardry.com

It looks like you’re instrumenting a whole page reload…? Can you run something closer to the metal? csswizardry.com/2022/08/meas...

csswizardry.comMeasure What You Impact, Not What You Influence – CSS WizardryWhen implementing performance fixes, it’s imperative that you measure the right thing—but what is ‘right’?

3/4/26, 4:01 pm0 reposts1 like

Nico Prat

@nicooprat.com

4 Apr

Also, I read this post too and found the way to measure CSS rendering time clever! Unfortunately I don’t think it’s possible with a Vue app as we don’t handle how styles are applied! We can’t just « wrap » stylesheets with scripts…

Nico Prat

@nicooprat.com

4 Apr

Indeed I was trying to see if applying those styles to off canvas navigation would make the initial page rendering faster, but it might not be the right approach. How would you do it? Capture only the open/close events for instance? Thanks.