Web platform features explorer

📃 June 2023 release notes

Newly available

The following features are newly available:

  • calc() keywords: The e, pi, infinity, and NaN keywords represent well-defined constants accepted in CSS math functions such as calc().
  • JavaScript modules in workers: The Worker() constructor accepts { type: "module" } to load scripts that use import and export. Also known as ECMAScript modules or ESM in workers.
  • window.print(): The window.print() method opens the browser's print dialog.

New in Edge

The following features are now available in Edge:

  • Idle detection: The IdleDetector API is used to notify a webpage of the user's idle, active, and locked state.
  • JSON source text access: To serialize and parse JSON in a lossless way, JSON.stringify() handles rawJSON values and JSON.parse()'s reviver callback takes a source context parameter.
  • overflow: overlay: The overflow: overlay CSS declaration is an alias to overflow: auto. Historically, it caused non-standard behavior, allowing scrollbars to overlay content without taking up layout space.
  • Partitioned cookies: Partitioned cookies allow you to opt a cookie into partitioned storage, with a separate cookie jar per top-level site. Also known as Cookies Having Independent Partitioned State or CHIPS.
  • scrollend: The scrollend event fires when an element or document has finished scrolling.
  • text-wrap: The text-wrap CSS property sets how lines break in text that overflows the container. It is a shorthand for text-wrap-style and text-wrap-mode.
  • text-wrap: balance: The text-wrap: balance CSS declaration balances the length of each line when text is broken into multiple lines. Also known as headline balancing.
  • text-wrap: nowrap: The text-wrap: nowrap CSS declaration prevents text breaking into multiple lines. Text that doesn't fit overflows instead.
  • Transferable ArrayBuffer: The transfer() and transferToFixedLength() methods of ArrayBuffer move a buffer from one context to another (for example, to a worker).
  • Extended constant expressions (WebAssembly): The i32.add, i32.sub, i32.mul, i64.add, i64.sub, and i64.mul operations extend constant expressions to include arithmetic.
  • Relaxed-width SIMD (WebAssembly): Relaxed SIMD (Single Instruction Multiple Data) introduces local non-determinism, where the results of the instructions may vary based on hardware support.
  • white-space-collapse: The white-space-collapse CSS property sets whether new line characters are shown as line breaks, and whether multiple consecutive spaces are all displayed or combined.

New in Firefox

The following features are now available in Firefox:

  • 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.
  • WebTransport: The WebTransport API transmits data between a client and a server, by using the HTTP/3 protocol.

New in Firefox for Android

The following features are now available in Firefox for Android:

  • 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.
  • WebTransport: The WebTransport API transmits data between a client and a server, by using the HTTP/3 protocol.