Firefox 150 release notes for developers (Beta)

Changes for web developers

APIs

DOM

• The options.shadowRoots argument of the Document.caretPositionFromPoint() method is now supported. This allows the method to return the node containing the caret from within a shadow DOM, provided its associated ShadowRoot was passed as an option. (Firefox bug 1914596).

• The non-standard caretRangeFromPoint() method of the Document interface is now supported. (Firefox bug 1550635).

• The ariaNotify() method is now supported on Document and Element. This queues a string of text to be announced by a screen reader, providing a more ergonomic and reliable alternative to ARIA live regions. (Firefox bug 2018095).

Changes for add-on developers

• The behavior of tabs.move is updated for split views so that:
  • The order of tabs in a split view can be swapped. (Firefox bug 2016762)
  • When the list of tabs includes both split view tabs and places one or more tabs between them, the tabs are moved apart and the split view closed. (Firefox bug 2022549)

Experimental web features

These features are shipping in Firefox 150 but are disabled by default. To experiment with them, search for the appropriate preference on the about:config page and set it to true. You can find more such features on the Experimental features page.

• Scoped custom element registries: dom.scoped-custom-element-registries.enabled

  The customElementRegistry property is supported on Document, Element, and ShadowRoot. This allows the definition of scoped custom element registries. (Firefox bug 2018900).