Web Platform Working Group Charter

The mission of the Web Platform Working Group is to continue the development of the HTML language and provide specifications that enable improved client-side application development on the Web, including application programming interfaces (APIs) for client-side development and markup vocabularies for describing and controlling client-side application behavior.

This proposed charter is available on GitHub. Feel free to raise issues.

Start date1 November 2016
End date 30 March 2018
Confidentiality Proceedings are Public
Chairs Adrian Bateman, Charles McCathie Nevile, Léonie Watson
Team Contacts
(FTE %: 100)
Yves Lafon, Xiaoqian Wu
Usual Meeting Schedule Teleconferences: There are generally not regular teleconferences.
Topic-specific calls may be held up to once per week if needed.
Face-to-face: we will meet during the W3C's annual Technical Plenary week; up to 2 other F2F meetings may be scheduled for the full group; Up to 4 meetings per year may be scheduled for subgroups working on specific topics.
IRC: active participants, particularly editors, regularly use the group's IRC channel(s)


The Web Platform Working Group was the result of merging the Web Applications Working Group and the HTML Working Group in 2015, with some deliverables moved to other groups. The work boundaries between the two Working Groups had narrowed over the years, given that it is difficult to introduce new HTML elements and attributes without looking at their implications at the API level.

The initial experiment in merging the group for 12 months suggests that it is a reasonable path to continue. This charter therefore provides an 18 month extension, removes some deliverables considered unlikely to progress within that period, and includes others but with a specific requirement that there is a prospect of success before work will continue within the Working Group.


The group will:

The Web Platform Working Group should develop modular specifications to the greatest extent possible for the development of the HTML language, allowing extension specifications to define new elements, new attributes, new values for attributes that accept defined sets of keywords, and new APIs.

Success Criteria

The group will be considered successful if it produces

  • Stable versions of specifications addressing the work items listed in the Milestones section, with normative conformance requirements for implementation,
  • A test suite for each deliverable, sufficiently broad to demonstrate interoperability,
  • and Implementation reports for deliverables showing adoption,

resulting in the ready availability of multiple, independent, interoperable implementations of each deliverable, including in browsers, authoring and validation tools, and usage on the Web.

If participants from fewer than three distinct browser-engine projects are participating in the group, its charter should be re-examined by the W3C.


Recommendation-Track Deliverables

The working group will work on the following W3C specifications:

Database and Offline Application APIs
A set of objects and interfaces for client-side database functionality. For more details, see the Web Platform WG Database API page. The following Database APIs are deliverables under this charter:
Indexed Database API (2nd Edition)
An API for a database of records holding simple values and hierarchical objects
Document Object Model (DOM)
A set of specifications defining objects and interfaces for interaction with a document's tree model. These deliverables include:
An update for DOM4
DOM defines a platform-neutral model for events and node trees.
DOM Parsing and Serialization
Parsing markup into a DOM, and serialize for export, an HTML or XML fragment or document.
High Level User Events
A specification to enable authors to support user interaction in Web applications easily without requiring specific hardware, platform, or input methodologies to be in use.
UI Events
Events typically implemented by interactive user agents for user interaction such as mouse and keyboard input.
UIEvents KeyboardEvent code Values
Identifying the physical key being pressed by the user.
UIEvents KeyboardEvent key Values
Information about the character generated by key events.
Editing APIs
Clipboard API and events
Expose common clipboard operations such as cut, copy and paste to Web Applications.
Selection API
APIs for selection, which allows users and authors to select a portion of a document or specify a point of interest for copy, paste, and other editing operations.
Input Events
A specification defining additions to events for text and related input to allow for the monitoring and manipulation of default browser behavior in the context of text editor applications and other applications that deal with text input and text formatting.
A specification defining new values for the contentEditable attribute.
Defines the behavior of the editing commands that can be executed with execCommand.
File API
An API that enables Web applications to select file objects and access their data. This replaces the File Upload specification.
APIs that allow Web applications to directly act on gamepad data.
Specifications to define the HTML language, HTML-specific APIs for interacting with in-memory representations of resources that use the HTML language, and to define normative requirements for browsers and other user agents which process HTML resources.
The core language of the World Wide Web: the Hypertext Markup Language (HTML). The HTML specification should be progressively modularized into separate documents or extension specifications. Note that many other Working Groups define extensions to HTML. These should be referenced from the HTML Extension specification
HTML Canvas 2D Context
An API for the 2D Context of the HTML canvas element.
HTML Accessibility API Mappings 1.0
How to map HTML elements and attributes to platform accessibility APIs.
Describing the use of ARIA attributes on HTML elements.
Widely-used attributes on HTML elements to provide metadata, e.g. as Schema.org or Dublin Core.
NOTE: The microdata DOM API is out of scope.
Manifest for Web applications
A JSON-based manifest, to provide metadata about a web application.
Specifications that allow network communications:
Service Workers
Persistently cache resources and handle all resource requests for an application via script, including when the network isn't available.
Web Sockets API
An API to use the Web Sockets protocol for two-way communication with a remote host.
Pointer Lock (2nd Edition)
Defines an API that provides scripted access to raw mouse movement data while locking the target of mouse events to a single element and removing the cursor from view.
Push API
An API that provides web applications scripted access to server-sent notifications.
Screen Orientation API
An API to enable reading or locking view orientation, and notification of view orientation state changes.
Web Components
Adding custom elements to a document, with well-defined behavior and rendering.
Custom Elements
Define and use new types of DOM elements in a document.
Shadow DOM
Functional boundaries between DOM trees and how these trees interact with each other within a document, enabling better functional encapsulation within the DOM.
Web Interface Definition Language (Web IDL)
Language bindings and types for Web interface descriptions.
Web Workers
An API that allows Web application authors to spawn background workers running scripts in parallel to their main page, allowing for thread-like operation with message-passing as the coordination mechanism.

Potential deliverables

The following deliverables may be developed as Recommendation track documents, if there is consensus in the Working Group that incubation suggests success:

Input Method (IME) API
An API that provides access to a (native) input method editor.
FileSystem API
A local sandboxed file system API exposed only to Web Applications.
Packaging on the Web
Defines an approach for creating packages of files for use on the web.
Quota Management API
An API for managing the amount of storage space (short- or long-term) available.
HTML Imports
A way to include and reuse HTML documents in another HTML document.
Web Background Synchronization
A specification describing a method that enables Web applications to synchronize data when next online.

Note: The list of specifications above were Recommendation Track documents in the previous charter. They are not statements about incubation success, but more example of the incubation process applied to the list of deliverables of the previous charter.

Each specification should detail any known security implications for implementers, Web authors, and end users.

The Web Platform WG will actively seek security, privacy, internationalization and accessibility review on all its specifications.

If a specification reaches Recommendation status the working group may work on, and deliver an updated version of the specification under this charter. Specifications may be moved to Recommendation and a subsequent version begun to facilitate the progress of other work which depends on a stable reference.

The Working Group will not adopt new proposals until they have matured through the Web Platform Incubator Community Group or another similar incubation phase. If the Working Group decides to add new Recommendation-track deliverables then it will recharter with changes to that new charter limited to just the changes in deliverables.

For current information on the list of deliverables and their status see the Web Platform WG Publication Status page.

2.1.1. Specification Maintenance

The working group will maintain errata and publish revisions, as necessary, for the following W3C Recommendations:

Other Deliverables

Other non-normative documents may be created such as:

  • Test suites for each specification
  • Primers for each specification
  • Requirements documents for new specifications
  • Non-normative schemas for language formats
  • Non-normative group notes

A comprehensive test suite for all features of a specification is necessary to ensure the specification's robustness, consistency, and implementability, and to promote interoperability between User Agents. Therefore, each specification must have a companion test suite, which should be completed before transition to Candidate Recommendation, and must be completed, with an implementation report, before transition from Candidate Recommendation to Proposed Recommendation. Additional tests may be added to the test suite at any stage of the Recommendation track, and the maintenance of a implementation report is encouraged.


The group's Publication Status document provides current data about all of the group's specifications. Although the group expects all of its active deliverables to progress during this charter period, the charter does not include detailed milestone data for each specification because such data is speculative and easily becomes out of date. The Working Group does expect the following to occur:

Dependencies and Liaisons

HTML depends on, and is depended on by, many specifications.

Many specifications in many Working Groups depend on WebIDL.

Web Sockets depends on work in the IETF's HyBi Working Group.

This working group depends on review of aspects such as accessibility, internationalisation, security, and privacy in its deliverables.

The Web Platform Working Group will keep contact with and where applicable request review from at least the following:

Accessible Platform Architectures Working Group
This Group ensures W3C specifications provide support for accessibility to people with disabilities.
Accessible Rich Internet Applications Working Group
WAI-ARIA, the Accessible Rich Internet Applications Suite, defines a way to make Web content and Web applications more accessible to people with disabilities and is integrated into HTML to improve the accessibility and interoperability of web content and applications.
Browser Testing and Tools Working Group
This group's Web Driver specification is of interest to the Web Platform WG.
Cascading Style Sheets Working Group
To collaborate on CSS-related aspects of specifications such as Shadow DOM.
Device and Sensors Working Group
To coordinate regarding APIs for device services.
Digital Publishing Interest Group
This group has a core interest in the manifest and packaging deliverables.
Internationalization Core Working Group
This group provides advice or review to ensure that specifications meet the needs of an international Web.
Pointer Events Working Group
This group creates DOM extension specifications and is interested in DOM Level 3 Events and UI Events.
Privacy Interest Group (PING)
The Web Platform WG will request review of specifications from this group.
SVG (Scalable Vector Graphics) Working Group
To help ensure SVG requirements for the Web Platform WG's deliverables are met. The HTML markup language supports embedding SVG content and provides support for the Canvas 2D Context API.
Technical Architecture Group
The Web Platform WG will ask the Technical Architecture Group to review specifications.
Web and Mobile Interest Group
This group may provide advice or review to ensure that Web Platform WG deliverables interact correctly in the context of Mobile applications.
Web and TV Interest Group
This Group may review existing work, as well as the relationship between services on the Web and media services, and identify requirements and potential solutions to ensure that the Web will function well with media.
Web Application Security Working Group
This Group develops security and policy mechanisms to improve the security of Web Applications, and enable secure cross-origin communication.
Web Performance Working Group
Many of their specifications extend Web Platform WG deliverables.
Web Platform Incubator Community Group
This group provides a venue for proposing, incubating and discussing new web platform features to prepare them for standardisation, often in the Web Platform WG.
Web Real-Time Communications Working Group
This group creates API specifications for Real-Time Communications in Web browsers.
Web Security Interest Group
The Web Platform WG will request review of specifications from this group.

External Groups

The Working Group may also collaborate with:

ECMA Technical Committee 39 (TC39)
This is the group responsible for ECMAScript standardization, and related ECMAScript features like E4X. As the Web Applications Working Group will be developing ECMAScript APIs, it should collaborate with TC39.
Internet Engineering Task Force
The IETF is responsible for defining robust and secure protocols for Internet functionality. A close relationship with the IETF HTTP work is crucial to ensuring the good design, deployment, and success of protocol-based APIs such as CORS and Web Sockets. This Working Group will rely upon review and parallel progress of associated specifications, and will keep pace with the IETF's HTTPbis group' work, conditional upon steady progress. The working group may also liaise with the IETFs security work, either directly or through its liaison with the W3C's Web Application Security Working Group.
Some deliverables are derived from specifications originally written at the WHATWG, or for which a version is maintained there. The Web Platform Working Group should make an effort to avoid differences between WHATWG and Web Platform WG specifications that harm interoperability on the Web.


To be successful, the Web Platform Working Group is expected to have 10 or more active participants for its duration, and to have the participation of industry leaders in fields relevant to the specifications it produces.

If participants from fewer than three distinct browser-engine projects are participating in the group, its charter should be re-examined by the W3C.

The Chairs, specification Editors and test Facilitators are expected to contribute one to two days per week towards the Working Group. There is no minimum requirement for other Participants.


The working mode of the group is described in detail on its wiki. In general the group does not hold plenary teleconferences, but does meet face to face at the TPAC. It may hold more meetings, and certain specifications are developed with regular teleconferences. Note the Decision Policy below with regards to meetings.

The Working Group conducts its work primarily through GitHub repositories.

The Group uses mailing lists. Subscription to these lists is open to the public, subject to W3C norms of behavior.

Up-to-date information about the group is available from the Web Platform Working Group home page.

Decision Policy

As required by the W3C Process Document (section 3.3), this group will seek to make decisions when there is consensus and with due process. The expectation is that, an editor or other participant makes an initial proposal, which is refined in discussion with members of the group and other reviewers, and consensus emerges with little formal voting being required.

If a decision is necessary for timely progress, but consensus is not achieved after careful consideration of the range of views presented, the Chairs may put a question out for voting within the group to allow for asynchronous participation, using the mechanism noted in the group's Work Mode documents, and record a decision, along with any objections. The matter should then be considered resolved unless and until new information becomes available.

Any resolution taken in a face-to-face meeting or teleconference is to be considered provisional until 10 (ten) working days after the publication of the resolutions in meeting minutes sent to the appropriate working group mailing list as described in the Work Mode documents. If no objections are raised on the mailing list within that time, the resolution will be considered to have consensus as a resolution of the Working Group.

This charter is written in accordance with Section 3.4, Votes of the W3C Process Document and includes no voting procedures beyond what the Process Document requires.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty-Free basis.

For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.


This Working Group will use the W3C Software and Document license for all its deliverables.

About this Charter

This charter for the Web Platform Working Group has been created according to section 5 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Changes from the previous charter

The major changes from the first Web platform Working Group charter include:

New deliverables:
Removed as deliverables:
Streams; URL; XHR1
Marked as deliverables to be taken up if incubation suggests likely success:
Background Synchronisation; Filesystem API; HTML Import; Input Methods; Packaging; Quota API

Yves Lafon, Team Contact
Xiaoqian Wu, Team Contact
Adrian Bateman, Chair
Charles McCathie Nevile, Chair
Léonie Watson, Chair