1. CSS Anchor Positioning

    Allows placing elements anywhere on the page relative to an "anchor element", without regard to the layout of other elements besides their containing block

  2. :has() CSS relational pseudo-class

    Select elements containing specific content. For example, `a:has(img)` selects all `<a>` elements that contain an `<img>` child.

  3. CSS Relative colors

    The CSS Relative Color syntax allows a color to be defined relative to another color using the `from` keyword and optionally `calc()` for any of the color values.

  4. rel=noopener

    Ensure new browsing contexts are opened without a useful `window.opener`

  5. relList (DOMTokenList)

    Method of easily manipulating rel attribute values on elements, using the DOMTokenList object (similar to classList).

  6. attr api: ownerelement

  7. document api: releasecapture

  8. document api: releaseevents

  9. focusevent api: relatedtarget

  10. htmlareaelement api: rel

  11. htmlareaelement api: rellist

  12. htmlbrelement api

  13. htmlformelement api: rel

  14. htmlformelement api: rellist

  15. htmlhrelement api

  16. htmlhrelement api: align

  17. htmlhrelement api: color

  18. htmlhrelement api: size

  19. htmlhrelement api: width

  20. htmllinkelement api: rel

  21. htmllinkelement api: rellist

  22. htmlmeterelement api

  23. htmlmeterelement api: high

  24. htmlmeterelement api: low

  25. htmlmeterelement api: min

  26. htmlmeterelement api: optimum

  27. location api: reload

  28. mlgraphbuilder api: relu

  29. navigation api: reload

  30. rtcdatachannel api: reliable

  31. svgaelement api: rel

  32. svgaelement api: rellist

  33. svgcursorelement api

  34. svgfefuncrelement api

  35. svgfilterelement api

  36. svgfilterelement api: height

  37. svgfilterelement api: href

  38. svgfilterelement api: width

  39. svgfilterelement api: x

  40. svgfilterelement api: y

  41. window api: releaseevents

  42. html element: area: `target="_blank"` implies `rel="noopener"` behavior

  43. html element: area: rel

  44. html element: area: rel: noopener

  45. html element: area: rel: noreferrer

  46. html element: a: `target="_blank"` implies `rel="noopener"` behavior

  47. html element: a: rel

  48. html element: a: rel: noopener

  49. html element: a: rel: noreferrer

  50. svg element: a: rel