Web technology sessions at WWDC23

WWDC23 is here, and with it, a host of announcements of new web technology shipping in WebKit on macOS, iOS, iPadOS, and visionOS — plus new features for Safari, Web Inspector and Safari Web Extensions. Seven sessions at WWDC23 go into detail, demonstrating new technology directly relevant to web developers. New videos will be released each day this week.

Tuesday, June 6

Three Safari windows floating in a room, almost reaching from floor to ceiling.

Meet Safari for spatial computing

Discover the web for visionOS and learn how people can experience your web content in a whole new way. Explore the unique input model powering this platform and learn how you can optimize your website for spatial computing. We’ll also share how emerging standards are helping shape 3D experiences for the web.

A web app for WebKit Blog shown on macOS Sonoma. With three other web apps as Stage Manager windows off to the side. And four web app icons in the doc. Plus a push notification coming in from the WebKit web app.

What’s new in web apps

Discover web apps for Mac — a powerful way to experience your website from the Dock. Learn how you can customize your web app to give people the best experience when they add your site. We’ll also share how to take advantage of push notifications and badging for web apps for Mac and Home Screen web apps for iOS and iPadOS.

Wednesday, June 7

iPhone simulator showing in macOS Sonoma. With a menu open showing

Rediscover Safari developer features

Get ready to explore Safari’s rich set of tools for web developers and designers. Learn how you can inspect web content, find out about Responsive Design Mode and WebDriver, and get started with simulators and devices. We’ll also show you how to pair with Vision Pro, make content inspectable in your apps, and use Open with Simulator in Responsive Design Mode to help you test your websites on any device.

Diagram with Safari 16.0 through 17.0 beta on a timeline from Sept 2022 to June 2023. With a word cloud of many CSS features lightly showing in the background.

What’s new in CSS

Explore the latest advancements in CSS. Learn techniques and best practices for working with wide-gamut color, creating gorgeous typography, and writing simple and robust code. We’ll also peer into the future and preview upcoming layout and typography features.

Thursday, June 8

Three logos — for JPEG XL, HEIC, & AVIF, and the words "Managed Media Source API" on a slide.

Explore media formats for the web

Learn about the latest image formats and video technologies supported in Safari 17. Discover how you can use JPEG XL, AVIF, and HEIC in your websites and experiences and learn how they differ from previous formats. We’ll also show you how the Managed Media Source API draws less power than Media Source Extensions (MSE) and explore how you can use it to more efficiently manage streaming video over 5G.

Friday, June 9

Web Inspector open in Safari 17 on macOS Sonoma.

What’s new in Web Inspector

Web Inspector provides a powerful set of tools to debug and inspect web pages, web extensions, and WKWebViews on macOS, iOS and iPadOS. We’ll share the latest updates, including improved typography inspection, editing tools for variable fonts, controls to emulate people’s preferences, element badges in the DOM node tree, and Symbolic breakpoints.

What’s new in Safari extensions

Learn about the latest improvements to Safari extensions. We’ll take you through new APIs, explore per-site permissions for Safari app extensions, and share how you can make sure your extensions work great in both Private Browsing and Profiles.