📃 May 2026 release notes

Newly available

The following features are newly available:

Container style queries: Container style queries with the @container at-rule apply styles to an element based on the values of custom properties of its container.
crisp-edges: The image-rendering: crisp-edges CSS declaration scales images to preserve lines without blurring.
JavaScript modules in shared workers: The SharedWorker() constructor accepts { type: "module" } to load scripts that use import and export. Also known as ECMAScript modules or ESM in shared workers.
:open: The :open CSS pseudo-class matches elements that have open states, like <details>, <dialog>, or <select>, based on their state.
Shared worker: The SharedWorker() constructor runs a script in its own thread, which can send and receive messages with other scripts running at the same origin.
text-decoration-skip-ink: all: The text-decoration-skip-ink: all CSS declaration forces interruptions in underlines and overlines where the line would cross a glyph. This contrasts with auto, which does not skip for CJK glyphs.
ToggleEvent source: The source property of a ToggleEvent object is the element which triggered the toggle event to fire for a popover, <dialog>, or <details> element, if applicable.

The following features are now widely available:

Clip path boxes: The fill-box, stroke-box, and view-box values for clip-path set an edge of the element's box to use as the clipping shape.
lh unit: The lh CSS length unit corresponds to the requested line height, the computed value of the line-height property. Some lines may be higher than this based on their content.
rlh unit: The rlh CSS length unit is a font-relative length relative to the line height of root element.
User activation: The navigator.userActivation API reveals whether the user has interacted with the page through an "activation" gesture such as a click, tap, or key press. User activation gated APIs (such as the fullscreen API) fail without user interaction, and this API allows you to predict such a failure.
:user-valid and :user-invalid: The :user-valid and :user-invalid pseudo-classes match form controls that have been marked as valid or invalid based on their validation constraints.

The following features are now available in Chrome:

LanguageModel: The LanguageModel API prompts an on-device language model. Also known as the Prompt API.

The following features are now available in Edge:

Language detector: The LanguageDetector API identifies the likely natural language that some text is written in. You can use this API to supplement machine translation when the source source language is not known.
Translator: The Translator API translates some text from one natural language to another, using machine translation.

The following features are now available in Firefox:

Anchor positioning: Anchor positioning places an element based on the position of another element. For example, you can place a tooltip next to the content it references.
Document picture-in-picture: The document picture-in-picture API creates an always-on-top window from arbitrary HTML content.
Web serial: The navigator.serial API communicates with devices over serial ports, such as microcontrollers.

The following features are now available in Firefox for Android:

Anchor positioning: Anchor positioning places an element based on the position of another element. For example, you can place a tooltip next to the content it references.

The following features are now available in Safari:

Hanging punctuation: The hanging-punctuation CSS property puts punctuation characters outside of the box to align the text with the rest of the document.
Origin: An Origin object represents an origin, as in a scheme, hostname, and port. You can use it to make same-site and same-origin comparisons.

The following features are now available in Safari on iOS:

Hanging punctuation: The hanging-punctuation CSS property puts punctuation characters outside of the box to align the text with the rest of the document.
Origin: An Origin object represents an origin, as in a scheme, hostname, and port. You can use it to make same-site and same-origin comparisons.