1. dataset & data-* attributes

    Method of applying and accessing custom data to elements.

  2. Attributes for form submission

    Attributes for form submission that may be specified on submit buttons. The attributes are: `formaction`, `formenctype`, `formmethod`, `formnovalidate`, and `formtarget`

  3. Srcset and sizes attributes

    The `srcset` and `sizes` attributes on `img` (or `source`) elements allow authors to define various image resources and "hints" that assist a user agent to determine the most appropriate image source to display (e.g. high-resolution displays, small monitors, etc).

  4. element api: attributes

  5. element api: gethtml: serializes `<` and `>` in attributes as `&lt;` and `&gt;` (see this spec issue)

  6. element api: innerhtml: serializes `<` and `>` in attributes as `&lt;` and `&gt;` (see this spec issue)

  7. element api: outerhtml: serializes `<` and `>` in attributes as `&lt;` and `&gt;` (see this spec issue)

  8. htmlelement api: attributestylemap

  9. mathmlelement api: attributestylemap

  10. shadowroot api: gethtml: serializes `<` and `>` in attributes as `&lt;` and `&gt;` (see this spec issue)

  11. shadowroot api: innerhtml: serializes `<` and `>` in attributes as `&lt;` and `&gt;` (see this spec issue)

  12. svgelement api: attributestylemap

  13. html element: img: aspect ratio computed from `width` and `height` attributes

  14. html element: video: aspect ratio computed from `width` and `height` attributes

  15. html attribute: `data-*` attributes

  16. javascript statement: import: import attributes with `assert` syntax (formerly import assertions)

  17. javascript statement: import: import attributes with `assert` syntax (formerly import assertions): `assert {type: 'css'}`

  18. javascript statement: import: import attributes with `assert` syntax (formerly import assertions): `assert {type: 'json'}`

  19. javascript statement: import: import attributes (`with` syntax)

  20. javascript statement: import: import attributes (`with` syntax): `with {type: 'css'}`

  21. javascript statement: import: import attributes (`with` syntax): `with {type: 'json'}`

  22. javascript statement: import: import attributes (`with` syntax): `with {type: 'text'}`

  23. global_attributes: autofocus

  24. global_attributes: class

  25. global_attributes: clip

  26. global_attributes: clip-path

  27. global_attributes: clip-rule

  28. global_attributes: color

  29. global_attributes: cursor

  30. global_attributes: direction

  31. global_attributes: display

  32. global_attributes: fill-rule

  33. global_attributes: filter

  34. global_attributes: font-size

  35. global_attributes: font-style

  36. global_attributes: id

  37. global_attributes: lang

  38. global_attributes: mask

  39. global_attributes: opacity

  40. global_attributes: overflow

  41. global_attributes: stroke

  42. global_attributes: style

  43. global_attributes: tabindex

  44. global_attributes: transform

  45. global_attributes: xml:lang

  46. global_attributes: xml:space