1. sandbox attribute for iframes

    Method of running external site pages with reduced privileges (e.g. no JavaScript) in iframes.

  2. seamless attribute for iframes

    The seamless attribute makes an iframe's contents actually part of a page, and adopts the styles from its hosting page. The attribute has been removed from both [the WHATWG](https://github.com/whatwg/html/issues/331) and [the W3C](https://github.com/w3c/html/pull/325) HTML5 specifications.

  3. srcdoc attribute for iframes

    Override the content specified in the `src` attribute (if present) with HTML content within the attribute.

  4. Lazy loading via attribute for images & iframes

    The `loading` attribute on images & iframes gives authors control over when the browser should start loading the resource.

  5. htmliframeelement api

  6. htmliframeelement api: align

  7. htmliframeelement api: allow

  8. htmliframeelement api: csp

  9. htmliframeelement api: fetchpriority

  10. htmliframeelement api: frameborder

  11. htmliframeelement api: height

  12. htmliframeelement api: loading

  13. htmliframeelement api: longdesc

  14. htmliframeelement api: marginheight

  15. htmliframeelement api: marginwidth

  16. htmliframeelement api: name

  17. htmliframeelement api: sandbox

  18. htmliframeelement api: scrolling

  19. htmliframeelement api: src

  20. htmliframeelement api: srcdoc

  21. htmliframeelement api: width

  22. html element: iframe

  23. html element: iframe: align

  24. html element: iframe: allow

  25. html element: iframe: allowfullscreen

  26. html element: iframe: allowpaymentrequest

  27. html element: iframe: aspect ratio computed from `width` and `height` attributes

  28. html element: iframe: external protocol urls blocked

  29. html element: iframe: fetchpriority

  30. html element: iframe: frameborder

  31. html element: iframe: height

  32. html element: iframe: loading

  33. html element: iframe: longdesc

  34. html element: iframe: marginheight

  35. html element: iframe: marginwidth

  36. html element: iframe: name

  37. html element: iframe: referrerpolicy

  38. html element: iframe: sandbox

  39. html element: iframe: `sandbox="allow-downloads"`

  40. html element: iframe: `sandbox="allow-modals"`

  41. html element: iframe: `sandbox="allow-popups"`

  42. html element: iframe: `sandbox="allow-popups-to-escape-sandbox"`

  43. html element: iframe: `sandbox="allow-presentation"`

  44. html element: iframe: `sandbox="allow-same-origin"`

  45. html element: iframe: `sandbox="allow-storage-access-by-user-activation"`

  46. html element: iframe: `sandbox="allow-top-navigation-by-user-activation"`

  47. html element: iframe: scrolling

  48. html element: iframe: src

  49. html element: iframe: srcdoc

  50. html element: iframe: width