Firefox 118 release notes for developers - Content

This article provides information about the changes in Firefox 118 that affect developers. Firefox 118 was released on September 26, 2023.

Changes for web developers

The {{HTMLElement('search')}} element is now supported. The <search> element is a group element that serves to contain all the elements used in a search or filtering operation (Firefox bug 1824121).

The {{cssxref("font-synthesis-position")}} property and position value for {{cssxref("font-synthesis")}} shorthand property are now supported. These allow subscript and superscript typefaces to be disabled for fonts that do not have glyphs for them when using {{cssxref("font-variant-position")}} (Firefox bug 1849010).
Multiple CSS math functions are now supported: abs(), sign(), round(), mod(), rem(), pow(), sqrt(), hypot(), log(), and exp() (Firefox bug 1814589).
A new keyword from-font in the CSS property font-size-adjust enables picking the desired <font-metric> from the first available font (Firefox bug 1708240).
The CSS property transform-box now supports the values content-box and stroke-box. For the reference box, the content-box value uses the content box and the stroke-box value uses the stroke bounding box that contains an SVG's shape (Firefox bug 1819464).
The CSS property font-size-adjust supports the keyword from-font that enables picking the desired <font-metric> from the first available font (Firefox bug 1708240).

No notable changes.

The HTTP Permissions-Policy header's publickey-credentials-get directive is now supported, which can be used to enable the Web Authentication API interface for retrieving public-key credentials in a cross-origin iframe (Firefox bug 1460986).

The <semantics> and <maction> elements only render the first child element by default now. The mathml.legacy_maction_and_semantics_implementations.disabled preference has been removed (Firefox bug 1788223).
All values of the mathvariant attribute other than normal are now deprecated. Additionally, the attribute's use is now limited to the <mi> element (Firefox bug 1845461).

The <kbd>⊞ Windows Logo</kbd> key on Windows and the <kbd>Command</kbd> key on macOS now return a value of "Meta" for KeyboardEvent.key, instead of "OS", and KeyboardEvent.code returns MetaLeft/MetaRight instead of OSLeft/OSRight (Firefox bug 1232918).
The {{domxref("RTCRtpTransceiver.currentDirection")}} and {{domxref("RTCRtpTransceiver.direction")}} properties now support the "stopped" value for indicating whether a transceiver has stopped. This value should now be used instead of the deprecated {{domxref("RTCRtpTransceiver.stopped")}} property (Firefox bug 1568296).
The array returned by {{domxref("RTCPeerConnection.getTransceivers()")}} now omits stopped transceivers. Similarly, {{domxref("RTCPeerConnection.getReceivers()")}} and {{domxref("RTCPeerConnection.getSenders()")}} omit the receivers and senders associated with a stopped transceiver (Firefox bug 1568296).
The TextMetrics.emHeightDescent and TextMetrics.emHeightAscent properties are now supported (Firefox bug 1841692).

Fixed an internal race condition for Android that caused the returned user prompt text to be empty for both WebDriver BiDi and Marionette (Firefox bug 1848167).
Both the WebDriver:PerformActions command in Marionette and the browsingContext.performActions command in WebDriver BiDi failed to correctly scroll for a wheel input source in environments that have a high-resolution display connected (Firefox bug 1849229).

Added the browsingContext.activate command that allows users to bring the given background tab into foreground (Firefox bug 1841004).
Added the browsingContext.handleUserPrompt command that allows users to accept or dismiss an open user prompt of type alert, confirm, or prompt (Firefox bug 1824197).
Added the browsingContext.userPromptOpened event that is emitted when a user prompt of type alert, confirm, or prompt was opened (Firefox bug 1824224).
Added a type field to the JSON payload that is returned to clients for identifying event messages or the success state of a command, which can be either success or error (Firefox bug 1844009).

Added support for all the Web Authentication extension commands, which allow users to authenticate themselves by Public Key Credentials (Firefox bug 1846574)

Support for browser_style in the manifest keys action, options_ui, page_action, and sidebar_action for Manifest V3 extensions has been removed (Firefox bug 1830711). See Browser Styles' Manifest v3 migration for information about transitioning from browser_style in Manifest V3 extensions.