HTML5.3: Candidate Recommendation (CR) exit criteria

Background: Process Requirements

According to the W3C Process, as part of the approval process for a specification to enter Candidate Recommendation (CR), the Working Group must:

1. Show that the specification has met all Working Group requirements, or explain why the requirements have changed or been deferred
2. Explain how the group proposes to demonstrate broad implementation experience.
3. Show the document has received wide review.

The review period for CR must be at least four weeks after publication, and should be longer for complex documents

1. Adequate implementation experience, described as

   the specification is sufficiently clear, complete, and relevant to market needs, to ensure that independent interoperable implementations of each feature of the specification will be realized
   https://www.w3.org/2015/Process-20150901/#implementation-experience

2. The document has received wide review.

HTML5.0, HTML5.1, and HTML5.2 have already been accepted by the Working Group, Advisory Committee, and W3C Director as meeting these requirements.

Meeting our requirements

There is not a formal requirements document for HTML5.3. HTML is an extremely widely implemented and widely-used technology, and we consider the requirements for this group to be documenting what is interoperable among the things considered "HTML" to enable implementers of user agents, developers of content creation and management tools, and producers of Web content to implement and use HTML interoperably with confidence.

HTML has continued to develop over the last 25 years, and we expect that process to continue. Therefore, rather than finishing "the HTML specification" we take as our task to regularly produce a W3C Recommendation that achieves the goal of documenting HTML more accurately and usefully than its predecessor, taking into account both changes in HTML and where possible improving the quality of the documentation itself.

Wide review

The HTML5 specification is perhaps the most widely reviewed product of W3C. We believe that the implementation in software, and concomitant use, generally constitutes sufficient review.

In addition, we actively seek review by the W3C Working Groups that specialize in accessibility, internationalisation, privacy, and security. We include a changelog with each regular Working Draft update, to help the general public easily identify relevant changes to the HTML specification.

Implementation experience

Since all previous versions of HTML have been accepted as showing implementation experience, we propose that no substantive changes that add features or requirements will be accepted unless they are implemented interoperably by at least 2 independent shipping products. Similarly, if a feature in the specification is identified as not having at least two interoperable shipping implementations it will be removed.

There is no requirement that all features must be implemented by a single product.

For the purposes of this criterion, we define the following terms:

Independent

Each feature or requirement implementation must be developed by a different party, and shipped as part of a different product. In particular, two products that re-use the same codebase to implement a particular feature or requirement will not be considered independent.

Interoperably

Features coded according to the specification must work "the same way" in different implementations. A test or test suite may be used to demonstrate this.

Shipping product

One which:

1. Implements the relevant conformance class of the specification, typically "web browsers and other interactive user agents" .
2. Is available to the general public. The implementation may be a shipping product or other publicly available version (for example a beta version, preview release or nightly build), endorsed by those who produced it as sufficiently stable.
3. Is intended for general public use, i.e. is not an experimental demonstration.

Entering and exiting CR

When the requirements for entering CR have been met, we will need to show a group decision that the current Working Draft for HTML5.3 is a notable improvement on the HTML5.2 Recommendation, has received sufficient review of changes, and is therefore ready to be proposed as a Recommendation.

Given the implementation-driven model for changes, that much of HTML5 has already been reviewed before we began the work, and that major features have been widely reviewed and implemented, the formal review period will be four weeks.

To exit CR, we will need to address comments received during the CR period, and show that the Working Group reached a decision that it has indeed met its working criteria, and addressed comments raised as per the Process.