Firefox 112 for developers

This article provides information about the changes in Firefox 112 that affect developers. Firefox 112 was released on April 11, 2023.

Changes for web developers


  • The HTMLElement property inert is now fully enabled. It allows the browser to ignore content or interactive elements that are within an HTMLElement with the inert attribute. See Firefox bug 1764263 for more details.



No notable changes.



  • Removes support for IDBMutableFile, IDBFileRequest, IDBFileHandle, and IDBDatabase.createMutableFile(). These interfaces are not present in any specification, have been behind a preference since version 102, and have been removed from the other main browser engines for some years. (Firefox bug 1500343.)

WebDriver conformance (WebDriver BiDi, Marionette)

WebDriver BiDi

  • Implemented the browsingContext.print command, which allows clients to request a rendered PDF document of the browsing context, represented as a Base64-encoded string. See Firefox bug 1806810 for more details.
  • Implemented script.addPreloadScript and script.removePreloadScript commands, which let test clients inject a functionality that's guaranteed to be available for any content scripts that are subsequently loaded, and before any later scripts that WebDriver injects into the context. See Firefox bug 1806420 and Firefox bug 1806465 for more details.
  • Element and ShadowRoot references as stored in the node cache can now be used in both Marionette and WebDriver BiDi by their exact same unique reference. See Firefox bug 1770733 for more details.
  • Removed isRedirect from the network events base parameters (Firefox bug 1819875).


  • Fixed an issue where the payload of a response was not wrapped within a value field based on certain data type. (Firefox bug 1819029).
  • Fixed an issue where WebDriver:ElementClear was emitting an extra change event for content editable elements (Firefox bug 1744925).

Changes for add-on developers

  • The properties usedDelegatedCredentials, usedEch, usedOcsp, and usedPrivateDns have been added to webRequest.SecurityInfo. These properties provide information about the security of the connection used for a web request (Firefox bug 1804460).
  • The property "type" is supported in the "background" manifest key. Setting this key to "module" loads background scripts specified with "scripts" as ES modules, avoiding the need to switch to background pages to use ES modules (Firefox bug 1811443).

Older versions