HTML5.3 Implementation report

This report outlines known implementations for the features added between HTML5.2 and HTML5.3. It is intended to demonstrate sufficient interoperability to justify moving HTML5.3 from Candidate Recommendation as required by W3C Process.

After that time it is unlikely to be updated, and people interested in the support of HTML features should instead look at the many resources on the Web that try to provide that information in an up-to-date form.

Last updated: 11 September 2018.

Implementation information is documented in the relevant GitHub issue, Pull Request (PR), or documentation for developers.


Blink (e.g. Chrome/Opera/Yandex/Vivaldi)Edge/EdgeHTMLFirefox/QuantumInternet Explorer/TridentSafari/WebkitNotes
Link to pull request, feature... ? ? ? ? ? Notes/tests/...
Added autocapitalize attribute Pass ? Fail ? Pass Terence
Added the as attribute Pass fail Pass ? fail Xiaoqian
Added allowUserMedia attribute to iframe pass fail fail fail fail will be replaced by feature policy
Added the ping attribute Pass Pass Pass Fail Pass
Added the integrity attribute from Sub-Resource Integrity pass pass pass ? pass Xiaoqian
Added disableRemotePlayback to HTMLMediaElement interface pass fail fail ? fail Xiaoqian
Added allowable context types for the canvas element Pass ? Pass ? ? Terence
Added fully internationalized email addresses ? ? Pass ? ? Chaals
Added focusin and focusout events ? ? ? ? ? Patricia
Added missing rel definitions ? ? ? ? ? Bruce
Added MacOS uniform type identifier for media-type registrations -- -- -- -- -- up to date with developer.apple.com
Added mandate for UTF-8 Pass ? Pass ? Pass
Added Window clipboard format for media-type registration -- -- -- -- -- up to date with MSDN Terence
Defines the rev IDL attribute Pass Pass Pass Pass ? Chaals
Added customised built-in elements Pass Fail Pass Fail ? Chaals
Added autonomous custom elements Pass Fail Pass Fail ? Chaals
add customElements property to the Window Object Pass ? Pass ? ? Tested manually with the console
caption end tag is not required Pass Pass Pass Pass ? Chaals
Adds capture attribute Pass Fail Pass Fail Pass tink
Only select a browsing context by name from within the unit of related browsing contexts ? ? ? ? ? chaals
Add decode() and decoding to HTMLImageElement Pass ? Fail Fail Pass Sangwhan
Make HTMLMediaElement.play() return a Promise Pass ? Pass ? Pass Sangwhan


Blink (e.g. Chrome/Opera/Yandex/Vivaldi)Edge/EdgeHTMLFirefox/QuantumInternet Explorer/TridentSafari/WebkitNotes
Deprecate object from forms Pass ? Pass ? pass Manual testing in Firefox, Chrome and Safari showed that object was associating to form elements by use of form attribute. Prose updated to indicate this is still valid for historical reasons.
Removed anchor-points section Fail Fail Fail Fail Fail No known implementations. Tested manually.
Removed magic alignment for the dialog element Fail Fail Fail Fail Fail No known implementations. Tested manually.
Removed requirement for XML srcdoc in xHTML Pass ? Pass ? ? Chaals
Removed "monkeypatch" for File API - - - - - removed from spec due to resolution of w3c/FileAPI#32 and updated specification defined in FileAPI.


Chrome/BlinkEdge/EdgeHTMLFirefox/QuantumInternet Explorer/TridentSafari/WebkitNotes
Clarified that the doctype is ignored for srcdoc ? ? ? ? ? Patricia
Hides nonce attribute pass fail fail ? fail Xiaoqian
loosen the rule of the rb element pass ? pass ? pass Xiaoqian