HTML 5.1

W3C Candidate Recommendation,


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 since the 3 May 2016 Public Working Draft.

Changes to match implementation or reflect lack of it
Add oncopy /oncut /onpaste handling
Remove usemap attribute on object
Remove requestAutoComplete
HTML Fragment serialisation doesn’t throw
Allow header and footer elements to be nested if each level is within a sectioning element
Make the algorithm for forming a table closer to what implementations do with them
Remove multiple attribute on input type="range"
Remove IntersectionObservers
Remove canvasProxy, setContext from canvas
Make behaviour for fractional step values in stepUp and stepDown match reality
Allow empty option elements
mousewheel is now wheel
Remove appCache
Remove MediaController and mediagroup attribute
Change menu/type attribute token from popup to context
Restore the rev attribute, used by RDFa, and e.g. Schema.org
Remove the nested section h1 outline model
Removed style scoped
Changes related to other specifications
Integrate HTML longdesc
Use closed blob from File API
Integrate Resource Hints
Update HTMLAllCollection to match Web IDL
Integrate the encoding specification
Provide hooks to integrate CSP, and Realms from ECMAScript
Fixes for specification bugs
value attribute of input type="submit" is translatable
added requestAnimationFrame
Having title, or writing email to a friend is not sufficient to make an img conformant if the img/alt attribute is missing
Fix the content model for time
Add HTMLMediaElement/srcObject

Changes since the 12 April 2016 Public Working Draft.

Changes to match implementation or reflect lack of it
Removed seamless attribute on iframe
Removed table sorting
Clarify that respecting user preferences for track selection is valid
Allow figcaption anywhere within a figure (not just first or last)
Remove special handling of isindex in form submission
Normative reference changes
Move from WCAG 1.0 to WCAG 2.0

Changes between the 12 April 2016 Public Working Draft and the 10 March 2016 Public Working Draft.

accesskey attribute only takes a single character
This is to match implementation in browsers better.
Add a callout to detach a media object in the media element load algorithm
This is to synchronise with MSE.
Remove microdata
There is a https://www.w3.org/TR/2013/NOTE-microdata-20131029/W3C Note describing Microdata as an extension.
Note that the attributes may be added back, referring to a Recommendation-track version of the extension, since there is a substantial amount of implementation.

Changes between the 10 March 2016 Public Working Draft and the 10 October 2015 Public Working Draft.

Full details of all changes since 12 January 2016 are available from the commit log of the w3c/html github repository. Note that a large number of changes made between 10 October and 12 January were copied direct from the whatwg/html repository.

Removed because implementation is not consistent and the idea didn’t make sense
form attribute on label element.
Removed for lack of implementation and to potentially improve before re-adding
accessKeyLabel IDL attribute.
Removed for lack of implementation
Blank alt on area elements with duplicate href attributes is no longer conformant.
Browsers don’t know about the user’s keyboard
Storage Mutex
hreflang andtype attributes on area links
document.cssElementMap and DOMElementMap interface
document.commands IDL
master commands concept in menuitem
Command API and related concepts
Focus navigation fixed
When navigating internally, the next search for a link etc starts from where the navigation moved to - no longer optionally.
main refers to the body
As opposed to be allowed multiple times in the page, for other elements
More ways p can be automatigically closed
redefine "fully active" for a document
Require that a document has its own browsing context to be fully active
change currentSrc for images which don’t resolve
From the absolute URL to the URL given to the resolver
a is non-interactive if it has no href attribute
Fix Collections
HTMLFormControlsCollection not used for collections of fieldset elements
Instead fieldset makes an HTMLCollection
namedItem is an HTMLCollection not HTMLOptionsCollection
Supported tokens
Define supported tokens for link types and dropzone as those that have an impact on processing
add supported tokens for rel
Allow more cross-origin…
Enable cross-origin track and EventSource
Allow cross-origin content for ImageBitmap in canvas
let frameElement return null
Transferable objects can go to different domains
Make content of time consistent
There were contradictory requirements, now it is phrasing content, or text
Integration with the ES job queue
Defining EnqueueJob() and NextJob in a monkeypatch to ECMAScript.
Add missing events
Events and APIs for tracking promise rejection
event-source-error error for media fetching
event-track-error and event-track-load
Make navigator.javaEnabled() a method
Table cleanups
Add specific types for HTML table elements
.tFoot an .createTFoot() always insert at the end
Disallow tfoot before tbody
Clear autoplay flag once autoplaying
Otherwise odd things happened if the network changed
Cleaning up toBlob in canvas
Make the toBlob() callback non-nullable
Rename fileCallback to blobcallback
CSP hooks
Add hooks for property on global object
for inline events, styles
inline elements
update specification links
Flip modes (remote/local) in loading media resources
make origin on HTMLHyperlinkElementUtils and Location readonly
meta refresh parsing
Match Gecko better
make ; optional
Clean up SVG in HTML
describe the flavour of SVG used in browsers
Make SVG title first child not last
Scroll restoration
Add scroll restoration preferences to history traversal
Clarify manual scrolling restoration
Take account of srclang when rendering track
Windows without browsing context
window.open() can return null
Add "noopener" to rel and window
Move HTTPS state from window to document
Drop some IDL attributes
[Exposed=Window] for HTMLHyperLinkElementUtils
[Exposed=Window, Worker] for DOMStringMap
IDL Date
Add IDL [SameObject] for some objects that return collections
Make script IDL attributes reflect
Remove "no exception" step from HAVE_METADATA
Fix mismatched HTMLMediaElement currentTime exception
If there is a current media controller it can still throw…
setInterval() timers clear too
Cleanup Fullscreen
rename menu type="popup" as menu type="context"
Support width="0"
For img and related elements, but not table cells

A description of substantial changes between the HTML 5.0 Recommendation of 2014 and the HTML 5.1 draft as it was in August 2015 is available as part of a separate document, that is no longer maintained.