Experimental features in Firefox

Mozilla 发布了测试的 nightly 版本,用于测试新的浏览器特性。实验性特性,例如所提议的可用的 Web 平台标准的实现。这个页面列出了 Firefox Nightly 中的一些新特性和启用方法等信息。在发布这些功能之前,你可以测试 Web 站点和应用程序,并确保一切都能与最新的 Web 技术功能协同工作。

你需要下载隔夜版或是开发者版,来测试下面这些实验性特性。

HTML

功能 Firefox Nightly Firefox 开发者版 Firefox 测试版 Firefox 发行版 Preference
日期和时间输入<input>日期时间 相关的输入类型提供的新用户界面 开启 (从 51 开始支持,从 55 开始默认开启) 开启 (从 51 开始支持) 关闭 (从 51 开始支持) --- dom.forms.datetime
<dialog> 包含与之交互的 DOM 元素的对话框元素。Implementation of modal dialogs and accessibility still missing. 关闭 (从 53 开始支持) 关闭 (从 53 开始支持) --- --- dom.dialog_element.enabled

CSS

功能 Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
Subgrids Disabled Disabled Disabled Disabled layout.css.grid-template-subgrid-value.enabled
Display stray control characters in CSS as hex boxes
This feature renders control characters (Unicode category Cc) other than tab (U+0009), line feed (U+000A), form feed (U+000C), and carriage return (U+000D) as a hexbox when they are not expected.
43 43 Disabled Disabled layout.css.control-characters.enabled or layout.css.control-characters.visible
Positioned CSS Masks
A subset of CSS Masks that includes longhand properties of CSS Masks (en-US), as well as a change in the shorthand property
51 51 53 Disabled Controlled by a compile flag (MOZ_ENABLE_MASK_AS_SHORTHAND).
The font-display descriptor for @font-face
To improve Web fonts performance, @font-face has an experimental font-display descriptor.
关闭
(available since 46)
关闭
(available since 46)
关闭
(available since 46)
关闭
(available since 46)
layout.css.font-display.enabled

font-variation-settings 属性
font-variation-settings 提供了 OpenType 或 TrueType 字体印刷特点的低级别的控制,by specifying the four letter axis names of the features you want to vary, along with their variation values.

关闭
(available since 53)
关闭
(available since 53)
关闭
(available since 53)
关闭
(available since 53)

layout.css.font-variations.enabled
Functions only in Mac OS Sierra (and later).

For the downloadable fonts on axis-praxis, you also need gfx.downloadable_fonts.keep_variation_tables (in Firefox 54 and later)

touch-action CSS 属性
The touch-action CSS property is part of the Pointer Events specification and allows you to specify how and in what way the user is able to manipulate an object by touch.
50 layout.css.touch_action.enabled

The shape-outside CSS property
The shape-outside CSS property is part of the CSS Shapes Module Level 1 specification and allows you to specify a float area causing inline contents to wrap around a shape.

Firefox currently implements the <shape-box> values (Firefox bug 1309467) as well as the circle() (Firefox bug 1311244), ellipse() (Firefox bug 1326406), and polygon() (Firefox bug 1326409) functions.

关闭
(available since 53)
layout.css.shape-outside.enabled
The contain CSS property
The contain CSS property is part of the CSS Containment Module Level 1 specification and allows you to indicate that an element and its contents are independent of the rest of the document tree, allowing user agents to optimize the rendering of a page.
关闭
(available since 45)
关闭
(available since 45)
关闭
(available since 45)
关闭
(available since 45)
layout.css.contain.enabled

The column-span CSS property
The column-span CSS property is part of the CSS Multi-column Layout Module specification and allows you to specify how many columns an element spans across.

Firefox currently only parses the property (Firefox bug 1339298), it's not actually implemented yet (Firefox bug 616436).

关闭
(recognized since 55, but not implemented yet)
layout.css.column-span.enabled
The frames() timing function
See The frames() class of timing-functions (en-US) for more details.
开启 N/A 关闭
(available since 55)
关闭
(available since 55)
None

JavaScript

See also ECMAScript Next support for implemented features of ECMAScript 2016 and later, that are not experimental and thus available without preferences in Firefox Release.

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
Additions to the ArrayBuffer object Adds the ArrayBuffer.transfer() that returns a new ArrayBuffer whose contents have been taken from the oldBuffer's data (spec). 36 Disabled Disabled Disabled None
TypedObject objects (spec) Enabled Disabled Disabled Disabled None
SIMD (specification and polyfill) Enabled Disabled Disabled Disabled None
ECMAScript modules Allows you to use native ECMAScript modules, for example defining modules with <script type="module">, defining fallback scripts with <script nomodule>, and importing code features that have been exported from modules. Disabled Disabled Disabled Disabled dom.moduleScripts.enabled

APIs

Canvas & WebGL

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
WEBGL_debug_renderer_info extension The WEBGL_debug_renderer_info (en-US) extension allows you to transmit information useful to help debugging problems to the server. 42 42 Disabled Disabled webgl.enable-debug-renderer-info
OffscreenCanvas The OffscreenCanvas interface provides a canvas that can be rendered off screen. It is available in both the window and worker contexts. Disabled (available since 44) Disabled (available since 44) Disabled (available since 44) Disabled (available since 44) gfx.offscreencanvas.enabled
Hit regions Whether the mouse coordinates are within a particular area on the canvas is a common problem to solve. The hit region API allows you define an area of your canvas and provides another possibility to expose interactive content on a canvas to accessibility tools. Disabled (available since 30) Disabled (available since 30) Disabled (available since 30) Disabled (available since 30) canvas.hitregions.enabled

DOM

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
Mac 上的 WebVR API 1.1
WebVR API 允许你控制并和使用虚拟现实设备。
Enabled Disabled Disabled Disabled dom.vr.enabled
游戏手柄扩展
The Gamepad Extensions provide access to additional functionality such as pose information in the case of WebVR controllers, and haptic actuator control (e.g. controller vibration hardware).
Enabled Enabled Enabled Disabled dom.gamepad-extensions.enabled
Experimental fetch controller/signal/observer interfaces
Also known as "cancellable fetch", these interfaces contain functionality to allow fetch request operations to be observed and controlled during their lifetimes.
Disabled
(Available since 55)
Disabled Disabled Disabled dom.fetchObserver.enabled and dom.fetchController.enabled (not in about:config by default; you must set them yourself).
FlyWeb
FlyWeb is a project at Mozilla focused on bringing a new set of APIs to the browser for advertising and discovering local-area web servers.
51 Disabled Disabled Disabled dom.flyweb.enabled
HTMLMediaElement.seekToNextFrame()
Part of an experimentation process around support non-real-time access to media for tasks including filtering, editing, and so forth, the HTMLMediaElement.seekToNextFrame() (en-US) advances the the current play position to the next frame in the media.
49
(Fundamental update in version 50)
49
(Fundamental update in version 50)
Disabled Disabled media.seekToNextFrame.enabled
GeometryUtils.getBoxQuads() (Firefox bug 917755) 31 31 Disabled Disabled layout.css.getBoxQuads.enabled
GeometryUtils.convertPointFromNode(),
GeometryUtils.RectFromNode(), and
GeometryUtils.convertQuadFromNode()
(Firefox bug 918189)
31 31 Disabled Disabled layout.css.convertFromNode.enabled
Node.rootNode
The Node.rootNode (en-US) property returns a Node object representing the topmost node in the tree, or the current node if it's the topmost node in the tree.
This feature is kept experimental as its naming poses Web compatibility problems. It will be renamed in the future.
48 48 Disabled Disabled dom.node.rootNode.enabled
Performance Observer API
The PerformanceObserver interface is used to observe performance measurement events and be notified of new performance entries as they are recorded in the browser's performance timeline.
49 Disabled Disabled Disabled dom.enable_performance_observer
WebVTT Regions API
WebVTT (en-US) regions are parts of the video viewport that provide a rendering area for WebVTT cues. The VTTRegion (en-US) is the interface exposing the WebVTT cues.
This interface is considered to be in flux and isn't therefore activated in any version by default.
Disabled
(Experimental implementation since version 30)
Disabled Disabled Disabled media.webvtt.regions.enabled
音频和视频轨道支持
Implements HTMLMediaElement.audioTracks and HTMLMediaElement.videoTracks.
Firefox doesn't support multiple audio or video tracks, preventing the most common use cases for these properties to work properly. That's why these properties are not activated by default in any version.
Disabled
(Experimental implementation since version 33)
Disabled Disabled Disabled media.track.enabled
Better value for Event.timestamp
The property Event.timestamp is returning a DOMHighResTimeStamp, which is now relative to the Unix epoch.
32 (Windows)
43 (Linux)
32 (Windows)
43 (Linux)
Disabled Disabled media.track.enabled
指针事件 50 Disabled Disabled Disabled dom.w3c_pointer_events.enabled
Pointer Events PointerEvent.tangentialPressure (en-US) and PointerEvent.twist (en-US) 54 Disabled Disabled Disabled dom.w3c_pointer_events.enabled
Intersection Observer API
The Intersection Observer API allows you to configure a callback that is called whenever one item, called a target, intersects either the device viewport or a specified element called.
Disabled
(available since 53)
dom.IntersectionObserver.enabled
Web Animations API: KeyframeEffect and KeyframeEffectReadOnly
The KeyframeEffectReadOnly.KeyframeEffectReadOnly() and KeyframeEffect.KeyframeEffect() (en-US) constructors can be used to clone existing KeyframeEffectReadOnly (en-US) object instances by being given the object to clone as their only parameter (see Firefox bug 1273784.)
52 52 Disabled Disabled None
PromiseRejectionEvent and related features
Providing a way to monitor and more finely control the rejection of Promises.
Disabled
(available since 55)
Disabled Disabled Disabled dom.promise_rejection_events.enabled
Payment Request API
为网络支付提供的一个 API。
Disabled
(available since 55)
Disabled
(available since 55)
Disabled
(available since 55)
Disabled
(available since 55)
dom.payments.request.enabled

WebRTC

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
TCP ICE candidates
ICE candidates that use TCP rather than UDP are considered during ICE negotiation.

Disabled
41

Enabled
54

Disabled
41
Disabled
41
Disabled
41
media.peerconnection.ice.tcp

开发者工具

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
Debugger rewrite in HTML 52 52 Disabled Disabled devtools.debugger.new-debugger-frontend
Console rewrite in HTML 52 Disabled Disabled Disabled devtools.webconsole.new-frontend-enabled
Experimental Performance tool options
Enables options in the UI for JIT optimizations, memory, etc.
41 Disabled Disabled Disabled devtools.performance.ui.experimental
Layout side panel
The Layout side panel allows to inspect and manage different CSS layout types like CSS Grid Layout.
Disabled
(available since 52)
Disabled
(available since 52)
Disabled
(available since 52)
Disabled
(available since 52)
devtools.layoutview.enabled

其他

Feature Firefox Nightly Firefox Developer Edition Firefox Beta Firefox Release Preference
添加到主屏幕 The icons, name, short_name, and theme_color fields of the Web App Manifest (if present) can now be as the source of the homescreen/apps window icons, apps window title, homescreen icon title, and apps window color (respectively) for "Add to home screen" (Firefox Mobile only). 关闭 (available since 53) 关闭 (available since 53) 关闭 (available since 53) 关闭 (available since 52) manifest.install.enabled
TLS 1.3 开启 开启 关闭 关闭 security.tls.version.max to 4

See also