WebKit Blog

WebKit Supports Nested CSS

Back in December, we wrote an article detailing three different options for CSS Nesting.

New WebKit features in Safari 15.4

With over 70 additions to WebKit, Safari 15.4 is packed with new web technologies, updates, and fixes.

WebKit Features in Safari 16.4

Today, we’re thrilled to tell you about the many additions to WebKit that are included in Safari 16.4.

Introducing Shadow DOM API

We’re pleased to announce that basic support for the new slot-based shadow DOM API is now available in the nightly builds.

WebKit is moving away from prefixes

WebKit’s new feature policy is to implement experimental features unprefixed, behind a runtime flag.

The web just gets better with Interop 2024

The web is amazing.

Declarative Shadow DOM

We’re pleased to announce that support for the declarative shadow DOM API has been added and enabled by default in Safari Technology Preview 162.

Introducing Custom Elements

A little over a year ago, we announced the introduction of slot-based shadow DOM API, a lightweight mechanism to encapsulate a DOM tree by allowing the creation of a parallel DOM tree on an element called a “shadow tree” that replaces the rendering of the element without modifying the regular DOM tree.

Safari now supports File System Access API with private origin

WebKit supports new API that makes it possible for web apps to create, open, read, and write files directly, or create directories and enumerate their contents.

Using: Has() as a CSS Parent Selector and much more

It’s been a long-standing dream of front-end developers to have a way to apply CSS to an element based on what’s happening inside that element.

A New Bytecode Format for JavaScriptCore

In revision r237547 we introduced a new bytecode format for JavaScriptCore (JSC).

Assembling WebAssembly

WebAssembly in WebKit.

Bringing Back Horizontal Rules in HTML Select Elements

In September 2023, Safari 17.0 on macOS shipped a small but interesting change to the <select> element.

New WebKit Features in Safari 12.1

There are many improvements and new web platform features in WebKit that are now available with the release of Safari 12.1, included with macOS Mojave 10.14.4 and iOS 12.2.

Implementing Vertical Form Controls

Safari 17.4 adds vertical writing mode support for form control elements across macOS, iOS, iPadOS, and visionOS.

Rolling the dice with CSS random()

Random functions in programming languages are amazing.

Speculation in JavaScriptCore

This post is all about speculative compilation, or just speculation for short, in the context of the JavaScriptCore virtual machine.

URL Parsing in WebKit

URLs have been used for decades now and you'd would think they would have consistent behavior…

Locking in WebKit

We recently replaced all spinlocks, OS-provided mutexes, and condition variables in WebKit with the new WTF::Lock and WTF::Condition — these new primitives have some cool properties.

News from WWDC22: WebKit Features in Safari 16 Beta

WebKit has had a big year, with over 162 new features and improvements shipping in WebKit browsers — including Safari 15.2, Safari 15.4, and Safari 15.5.

Help choose the syntax for CSS Nesting

The CSS Working Group is continuing a debate over the best way to define nesting in CSS.

The HTML5 Parsing Algorithm

Announcing ... MathML! (WebKit)

If you’ve been following check-ins for the last year or so, then you already know that some dedicated contributors have been working on a MathML implementation in WebKit.