Firefox 113 for developers

This article provides information about the changes in Firefox 113 that affect developers. Firefox 113 was released on May 09, 2023.

Changes for web developers


No notable changes.



No notable changes.


Media, WebRTC, and Web Audio


  • The deprecated and non-standard CanvasRenderingContext2D.mozTextStyle attribute was permanently removed. This was previously hidden behind a preference. (Firefox bug 1294362).
  • The deprecated and non-standard attributes mozRTCPeerConnection, mozRTCIceCandidate, and mozRTCSessionDescription were permanently removed (Firefox bug 1531812).

WebDriver conformance (WebDriver BiDi, Marionette)

WebDriver BiDi

  • Added support for serializing Node objects within a Shadow DOM and the shadowRoot property on Node objects (Firefox bug 1802137).
  • Added support for cached responses for the network.responseStarted and network.responseCompleted events (Firefox bug 1806802 and Firefox bug 1806794).
  • Fixed an issue where the browsingContext.domContentLoaded and browsingContext.load events were missing for navigations using and document.close() (Firefox bug 1822772).
  • Fixed an issue where the script.callFunction command was throwing an invalid argument error if an unknown object was passed as an argument, instead of the expected no such handle error (Firefox bug 1821039).


  • The moz:useNonSpecCompliantPointerOrigin capability is now deprecated and will be fully removed in Firefox 116 (Firefox bug 1824911).
  • Implemented the WebDriver:FindElementFromShadowRoot and WebDriver:FindElementsFromShadowRoot commands (Firefox bug 1700095).
  • Implemented the WebDriver:GetComputedLabel and WebDriver:GetComputedRole commands (Firefox bug 1585622).
  • Added support for the background parameter of the WebDriver:Print command (Firefox bug 1783086).
  • Added support for the orientation parameter of the WebDriver:Print command (Firefox bug 1791819).
  • Fixed an issue with DOMTokenList instances, which are now returned as collections instead of arbitrary objects (Firefox bug 1823464).

Changes for add-on developers

Older versions