HTML, CSS & Accessibility

What is ARIA?

Matthew Edgar September 19, 2025

While testing AI agents on websites recently, I’ve noticed something interesting: the reasoning steps sometimes mention ARIA tags. What exactly are ARIA tags? What do we need to know about them? Should we use them? ARIA (Accessible Rich Internet Applications) is part of web accessibility.

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Use H1 Tags

Matthew Edgar August 5, 2024

Should you use H1 tags (or other header tags)? Are header tags required for SEO? Like so many technical SEO topics, these questions have a complex, nuanced answer..

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Chrome DevTools: Unused CSS

Matthew Edgar March 31, 2024

Unused CSS or JavaScript code will slow your website and can worsen Core Web Vitals metrics. How do you find how much unused code there is on your website? One way to find unused CSS or JavaScript code is in Chrome DevTools.

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Consolidate JavaScript or CSS Files

Matthew Edgar February 1, 2024

A typical speed recommendation is to consolidate (or concatenate) multiple JavaScript or CSS files into a single file. Does this still make sense? The idea is that consolidating multiple files into a single file reduces how many requests need to be made when the browser/robot is loading a webpage.

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