1. Brotli Accept-Encoding/Content-Encoding

    More effective lossless compression algorithm than gzip and deflate.

  2. contenteditable attribute (basic support)

    Method of making any HTML element editable.

  3. Content Security Policy 1.0

    Mitigate cross-site scripting attacks by only allowing certain sources of script, style, and other resources.

  4. Content Security Policy Level 2

    Mitigate cross-site scripting attacks by only allowing certain sources of script, style, and other resources. CSP 2 adds hash-source, nonce-source, and five new directives

  5. CSS content-visibility

    Provides control over when elements are rendered, so rendering can be skipped for elements not yet in the user's viewport.

  6. CSS display: contents

    `display: contents` causes an element's children to appear as if they were direct children of the element's parent, ignoring the element itself. This can be useful when a wrapper element should be ignored when using CSS grid or similar layout techniques.

  7. CSS Generated content for pseudo-elements

    Method of displaying text or images before or after the given element's contents using the ::before and ::after pseudo-elements. All browsers with support also support the `attr()` notation in the `content` property.

  8. DOMContentLoaded

    JavaScript event that fires when the DOM is loaded, but before all page assets are loaded (CSS, images, etc.).

  9. CSS Flexible Box Layout Module

    Method of positioning elements in horizontal or vertical stacks. Support includes all properties prefixed with `flex`, as well as `display: flex`, `display: inline-flex`, `align-content`, `align-items`, `align-self`, `justify-content` and `order`.

  10. HTMLElement.innerText

    A property representing the text within a DOM element and its descendants. As a getter, it approximates the text the user would get if they highlighted the contents of the element with the cursor and then copied to the clipboard.

  11. CSS justify-content: space-evenly

    The "space-evenly" value for the `justify-content` property distributes the space between items evenly. It is similar to space-around but provides equal instead of half-sized space on the edges. Can be used in both CSS flexbox & grid.

  12. SDCH Accept-Encoding/Content-Encoding

    Shared Dictionary Compression over HTTP

  13. contentindex api

  14. contentindexevent api

  15. contentindexevent api: id

  16. contentindex api: add

  17. contentindex api: delete

  18. contentindex api: getall

  19. contentvisibilityautostatechangedevent api

  20. contentvisibilityautostatechangedevent api: skipped

  21. document api: contenttype

  22. css property: content

  23. html element: content

  24. headers http header: content-disposition

  25. headers http header: content-encoding

  26. headers http header: content-language

  27. headers http header: content-length

  28. headers http header: content-location

  29. headers http header: content-range

  30. headers http header: content-security-policy-report-only

  31. headers http header: content-security-policy: base-uri

  32. headers http header: content-security-policy: child-src

  33. headers http header: content-security-policy: connect-src

  34. headers http header: content-security-policy: default-src

  35. headers http header: content-security-policy: font-src

  36. headers http header: content-security-policy: form-action

  37. headers http header: content-security-policy: frame-src

  38. headers http header: content-security-policy: img-src

  39. headers http header: content-security-policy: manifest-src

  40. headers http header: content-security-policy: media-src

  41. headers http header: content-security-policy: object-src

  42. headers http header: content-security-policy: prefetch-src

  43. headers http header: content-security-policy: referrer

  44. headers http header: content-security-policy: report-to

  45. headers http header: content-security-policy: report-uri

  46. headers http header: content-security-policy: sandbox

  47. headers http header: content-security-policy: script-src

  48. headers http header: content-security-policy: style-src

  49. headers http header: content-security-policy: worker-src

  50. headers http header: content-type