HTML 5.2: Changes

Changes

This section summarises substantial substantive changes between Public Working Drafts, as a guide for general review.

Full details of all changes since 12 January 2016 are available from the commit log of the w3c/html github repository, including various editorial and linking fixes.

Changes between Working Draft 7 and Working Draft 6

Better explanation for refresh rate: Improves explanation of refresh rate; requires browsers do not set arbitrary upper limits.
Update accesskey definition: Updates accesskey to require a single printable character.
Allow multiple main elements: Allows multiple main elements when only one is visible.
Added floating time warning: Adds warning about implicit switch to incremental time values with a time zone of UTC, for the type attribute in the datetime-local state.
Makes canonical a standard rel token: Adds canonical to the list of standard rel attribute tokens.

Changes between Working Draft 6 and Working Draft 5

Allow role="presentation" on img: Allows the ARIA presentation role to be applied to the img element.
Fix summary activation algorithm: Removes the step that aborts activation if the summary element is not the first child of the details element, and clarifies that only the first summary element inside a details element is an interactive element.
Guidance for UI filtering for suggestions: Recommends substring matching on the label attribute of the option element.
Update button element definition: Improves clarity and readability of the button element definition.
Updating summary element rendering: Updates recommended CSS rendering for the summary element, and removes rendering expectations for a summary element that is not a child of the details element.
Make style in body conforming: Adds a note to remove the restriction for the style element being in the head element (with a warning that using the style element in the body element can have unexpected consequences); and adds the style element to the set of flow content elements for the body element.
Clarified restrictions on children of p elements: Clarifies that child elements of the p element cannot be inline blocks, inline tables, or floated and positioned block-level elements.
Make HTML4/xHTML1 strict doctypes non-conforming: Disallows the use of the HTML4 and xHTML 1.1 strict doctypes.
Clarify where to propose rel extensions: References the correct part of the Microformats wiki, and adds a note to indicate proposals can also be filed against this HTML specification.
Remove references to Polyglot Markup: Removes references to the Polyglot Markup specification (now published as a W3C Note).
Make menu and menuitem match reality: Removes the radio and checkbox types for menus; requires that menuitem has content; menuitem makes a command if it is labelled; changes terminology from "popup menu" state to "context menu" state.

Changes between Working Draft 5 and Working Draft 4

Added 'creator context security': Defines a new 'creator context security' concept, which replaces the 'creator document' concept that Secure Context used to rely on
Updated dfn text: Refines terminology, and allows li as ancestor
Corrected row/col header algorithm: Corrected conditions for determining table row/column headers
Removed showModalDialog: Removes the showModalDialog method, which is being made obsolete in browsers
Added noopener link relation: Adds the noopener link relation, a requirement of Secure Context
Made surearea can be activated other than with pointer: Tightens up the requirement for interaction with area
Removed references to BE CSS (notions of binding): Removes references to the binding property proposed in the defunct Behavorial Extensions to CSS specification
Removed references to event parent: Completes removal of <iframe seamless>
Allowed div as child of dl: Allows the div element as a direct child of the dl element

Changes between Working Draft 4 and Working Draft 3

Add manifest attribute

Added the manifest attribute (specifies the location of the document’s cache manifest) to the html element.

Added iframe allowpaymentrequest attribute

Added the allowpaymentrequest attribute (used by the Payment Request API to determine if Document objects in an iframe element’s browsing context are to be allowed to make payment requests) to the iframe element.

Integrated WHATWG changes

Included:

Reflecting a broken URL should return the unparsed value
Add MathML and SVG to dependencies and cross reference them correctly
Resetting a textarea should reset its dirty value flag
remove domain to ascii term
Add recursion check to frame elements* Make document.open() and close() check for XML document
Change data type for HashChageEvent to match reality* Make marker of summary inside
Make selection members nullable types

Add definition of allowed to use

Added steps for determining whether a Document object document is allowed to use the feature indicated by attribute name

Add advisement about HTML manifest removal plans

Added an advisement that manifest-based application cache feature is in the process of being removed from the web platform.

Allow <link rel="apple-touch-icon sizes...>

Added the apple-touch-icon keyword to the rel attribute values required for the size attribute to be used on the link element.

Final changes for a clean section 3

Includes:

Adding innerText attribute
Removal of restrictions on BiDi algorithm section

Changes between Working Draft 3 and Working Draft 2

Allow headings within legend: This was proposed in issue #724, to enable better semantic markup. It works already in practice.
Incorporate blocking of element loading based on type, from [CSP3]
Updated allowed ARIA roles for form controls and many other elements: This matches the normative ARIA in HTML specification [html-aria].
Update ARIA version to match [wai-aria-1.1]: This allows some more roles, states and properties for improved accessibility
Describe real behaviour for elements made focusable by addon tabindex: This change is to describe real implementation in browsers, which unfortunately does not reflect the desirable behaviour earlier specified.
Tighten restrictions on navigation control for sandboxed contexts

Changes between Working Draft 2 and the First Public Working Draft

Treat data: URLs as a separate origin: data: URLs will have a unique, opaque origin rather than inheriting that of the settings object. This aligns with Blink / Gecko / Webkit behaviour
Various fixes for compatibility with WHATWG specification: Reflecting a broken URL should return the unparsed value; Allow currentScript to return SVGScriptElement; Resetting a textarea should reset its dirty value flag; Make document.open() and close() check for XML document; Change data type for HashChangeEvent to match reality; Make selection members nullable types; Formalize bogus comment state
Add about:html-kind URL definition: This allows for MP4 media track integration
Add nonce to link: For use in Content Security Policy [CSP3]
Add WindowOrWorkerGlobalScope mixin: A convenience that simplifies adding functionality for Window and WorkerGlobalScope objects
Make label-less empty option okay as a datalist child
caption element cannot take role values

Changes since HTML 5.1 - Note that these may change if the HTML 5.1 specification is updated.

toolbar type for menu: This was removed from HTML 5.1 for lack of implementation, and may be removed from HTML 5.2 if not implemented.
dialog element: This was removed from HTML 5.1 for lack of implementation, and may be removed from HTML 5.2 if not implemented.
registerContentHandler(), isContentHandlerRegistered() and isProtocolHandlerRegistered(): These were removed from HTML 5.1 for lack of implementation, and may be removed from HTML 5.2 if not implemented.
datetime value for type
This was removed from HTML 5.1 for lack of implementation, and may be removed from HTML 5.2 if not implemented.
inputmode: This was removed from HTML 5.1 for lack of implementation, and may be removed from HTML 5.2 if not implemented.
keygen has been removed: As per Working Group decision, since it is likely to be removed soon from at least one of the two remaining implementations.
Modules, for scripts