Firefox 108 for developers

This article provides information about the changes in Firefox 108 that will affect developers. Firefox 108 is the current Beta version of Firefox and will ship on December 13, 2022.

Changes for web developers

HTML

  • The <source> element supports height & width attributes when it is a child of a <picture> element. This functionality can be configured via the dom.picture_source_dimension_attributes.enabled preference which is now set to true by default (bug 1795953).

Removals

CSS

  • Trigonometric functions are now enabled with the layout.css.trig.enabled preference set to true by default. This allows the use of sin(), cos(), tan(), asin(), acos(), atan(), and atan2() functions (bug 1774589, bug 1787070).
  • CSS <calc-constant> type is implemented to allow for well-known constants such as pi and e within math functions (bug 1682444, bug 1787070).
  • Container query length units are now supported via the the layout.css.container-queries.enabled preference, which is set to false by default. Setting this preference to true allows the use of cqw, cqh, cqi, cqb, cqmin, and cqmax units of length which are relative to the size of a query container. For more information on these units, see the CSS Container Queries documentation (bug 1744231).

Removals

JavaScript

Removals

HTTP

Removals

Security

Removals

APIs

DOM

Media, WebRTC, and Web Audio

Removals

WebAssembly

Removals

WebDriver conformance (WebDriver BiDi, Marionette)

WebDriver BiDi

Marionette

Changes for add-on developers

  • Firefox now issues a warning when an extension is installed if its version number doesn't follow the recommended format (bug 1793925).

Removals

Other

Older versions