1. :dir() CSS pseudo-class

    Matches elements based on their directionality. `:dir(ltr)` matches elements which are Left-to-Right. `:dir(rtl)` matches elements which are Right-to-Left.

  2. CSS Environment Variables env()

    Usage of environment variables like `safe-area-inset-top`.

  3. CSS Filter Effects

    Method of applying filter effects using the `filter` property to elements, matching filters available in SVG. Filter functions include blur, brightness, contrast, drop-shadow, grayscale, hue-rotate, invert, opacity, sepia and saturate.

  4. CSS3 text-align-last

    CSS property to describe how the last line of a block or a line right before a forced line break when `text-align` is `justify`.

  5. ECMAScript 5

    Full support for the ECMAScript 5 specification. Features include `Function.prototype.bind`, Array methods like `indexOf`, `forEach`, `map` & `filter`, Object methods like `defineProperty`, `create` & `keys`, the `trim` method on Strings and many more.

  6. KeyboardEvent.location

    A `KeyboardEvent` property that indicates the location of the key on the input device. Useful when there are more than one physical key for the same logical key (e.g. left or right "Control" key; main or numpad "1" key).

  7. String.prototype.padStart(), String.prototype.padEnd()

    The `padStart()` and `padEnd()` methods pad the current string with a given string (eventually repeated) so that the resulting string reaches a given length. The pad is applied from the start (left) of the current string for `padStart()`, and applied from the end (right) of the current string for `padEnd()`.

  8. domrectreadonly api: right

  9. screen api: mozbrightness

  10. textmetrics api: actualboundingboxright

  11. vrfieldofview api: rightdegrees

  12. vrframedata api: rightprojectionmatrix

  13. vrframedata api: rightviewmatrix

  14. css property: -moz-outline-radius-bottomright

  15. css property: -moz-outline-radius-topright

  16. css property: border-bottom-right-radius

  17. css property: border-bottom-right-radius: elliptical corners

  18. css property: border-bottom-right-radius: percentages

  19. css property: border-right

  20. css property: border-right-color

  21. css property: border-right-style

  22. css property: border-right-width

  23. css property: border-top-right-radius

  24. css property: border-top-right-radius: elliptical corners

  25. css property: border-top-right-radius: percentages

  26. css property: caption-side: non-standard values `left`, `right`, `top-outside`, and `bottom-outside`

  27. css property: --*: `env()`: safe area inset variable `safe-area-inset-right`

  28. css property: justify-content: supported in flex layout: `left` and `right`

  29. css property: margin-right

  30. css property: margin-right: `auto`

  31. css property: padding-right

  32. css property: right

  33. css property: scroll-margin-right

  34. css property: scroll-padding-right

  35. css property: text-align: prefixed `center`, `left`, and `right` values for block alignment

  36. css property: text-combine-upright

  37. css property: text-combine-upright: `digits`

  38. css property: text-emphasis-position: `left` and `right`

  39. css property: text-underline-position: `left` and `right`

  40. css property: touch-action: `pan-up`, `pan-down`, `pan-left` and `pan-right`

  41. css selector: right-hand page pseudo-class (`:right`)

  42. types: filter-function: `brightness()`

  43. html element: body: rightmargin

  44. javascript built-in: array: reduceright

  45. javascript built-in: regexp: `regexp.rightcontext` (`$'`)

  46. javascript built-in: typedarray: reduceright

  47. javascript operator: bitwise right shift (`a >> b`)

  48. javascript operator: right shift assignment (`x >>= y`)

  49. javascript operator: bitwise unsigned right shift (`a >>> b`)

  50. javascript operator: unsigned right shift assignment (`x >>>= y`)