Weekly Platform News: HTML Loading Attribute, the Main ARIA Specifications, and Moving from iFrame to Shadow DOM

In this week’s roundup of platform news, Chrome introduces a new attribute for loading, accessibility specifications for web developers, and the BBC moves visualizations to the Shadow DOM.

Chrome ships the loading attribute

The HTML loading attribute for lazy-loading images and iframes is now supported in Chrome. You can add loading="lazy" to defer the loading of images and iframes that are below the viewport until the user scrolls near them.

Google suggests either treating this feature as a progressive enhancement or using it on top of your existing JavaScript-based lazy-loading solution.

This feature has not yet been added to the HTML Standard (but there is an open pull request), and multiple links to Google’s documentation are listed on its Chrome Status page.

(via web.dev)


Overview of ARIA specifications

The main accessibility specifications for web developers:

Name Description
ARIA in HTML Defines which ARIA role, state, and property attributes are allowed on which HTML elements (the implicit ARIA semantics are defined here)
Using ARIA Provides practical advice on how to use ARIA in HTML, with an emphasis on dynamic content and advanced UI controls (the “five rules of ARIA use” are defined here)
ARIA (Accessible Rich Internet Applications) Defines the ARIA roles, states, and properties
ARIA Authoring Practices Provides general guidelines on how to use ARIA to create accessible apps (includes ARIA implementation patterns for common widgets)
HTML Accessibility API Mappings Defines how browsers map HTML elements and attributes to the operating system’s accessibility APIs
WCAG (Web Content Accessibility Guidelines) Provides guidelines for making web content more accessible (success criteria for WCAG conformance are defined here)

Related: “Contributing to the ARIA Authoring Practices Guide” by Simon Pieters and Valerie Young


Shadow DOM on the BBC website

The BBC has moved from