Firefox 98 release notes for developers

This article provides information about the changes in Firefox 98 that affect developers. Firefox 98 was released on March 8, 2022.

Changes for web developers

HTML

• The HTML {{HTMLElement("dialog")}} element is now available by default. This element and its associated DOM APIs provide support for HTML-based modal dialog boxes (Firefox bug 1733536).

CSS

• The {{cssxref("hyphenate-character")}} property sets a string that is used instead of a hyphen character (-) at the end of a hyphenation line break (Firefox bug 1751024).

JavaScript

No notable changes

APIs

• {{domxref("navigator.registerProtocolHandler()")}} can now register protocol handlers for the ftp, sftp, and ftps schemes (Firefox bug 1705202).

DOM

• {{domxref("HTMLElement.outerText")}} is now supported (Firefox bug 1709790).
• The properties colorSpaceConversion, resizeWidth and resizeHeight can be passed to the method {{domxref("Window.createImageBitmap()")}} and {{domxref("WorkerGlobalScope.createImageBitmap()")}} using the options object (Firefox bug 1748868 and Firefox bug 1733559).
• {{domxref("ElementInternals")}} now has new form-associated custom element methods and properties that allow custom elements to interact with a form. These include the {{domxref("ElementInternals.form","form")}}, {{domxref("ElementInternals.labels","labels")}} and {{domxref("ElementInternals.willValidate", "willValidate")}} properties, and the {{domxref("ElementInternals.setFormValue()","setFormValue()")}} method. (Firefox bug 1556362, Firefox bug 1556373, Firefox bug 1556365, Firefox bug 1556449).

Removals

• The deprecated WebVR API is now disabled by default on all builds (previously it was enabled on Windows, macOS, and all nightly/dev builds). It can be re-enabled in about:config by setting dom.vr.enabled to true (Firefox bug 1750902).

WebDriver conformance (Marionette)

• Improved initial page load checks for newly opened tabs (Firefox bug 1747359).

Changes for add-on developers

• Web extensions using {{WebExtAPIRef("webRequest")}} were started early during Firefox startup. This has changed to only trigger early start-up for extensions using {{WebExtAPIRef("webRequest")}} blocking calls. Non-blocking calls no longer cause the early startup of an extension. (Firefox bug 1749871)
• cookieStoreId added to {{WebExtAPIRef("userScripts.register")}}. This enables extensions to register container-specific user scripts (Firefox bug 1738567).