1. ECMAScript 2015 (ES6)

    Support for the ECMAScript 2015 specification. Features include Promises, Modules, Classes, Template Literals, Arrow Functions, Let and Const, Default Parameters, Generators, Destructuring Assignment, Rest & Spread, Map/Set & WeakMap/WeakSet and many more.

  2. async attribute for external scripts

    The boolean async attribute on script elements allows the external JavaScript file to run when it's available, without delaying page load first.

  3. defer attribute for external scripts

    The boolean defer attribute on script elements allows the external JavaScript file to run when the DOM is loaded, without delaying page load first.

  4. Efficient Script Yielding: setImmediate()

    Yields control flow without the minimum delays enforced by setTimeout

  5. document api: scripts

  6. scriptprocessornode api

  7. scriptprocessornode api: `audioprocess` event

  8. scriptprocessornode api: buffersize

  9. serviceworker api: scripturl

  10. html element: script

  11. html element: script: attributionsrc

  12. html element: script: blocking

  13. html element: script: crossorigin

  14. html element: script: fetchpriority

  15. html element: script: integrity

  16. html element: script: nomodule

  17. html element: script: referrerpolicy

  18. html element: script: referrerpolicy: no-referrer-when-downgrade

  19. html element: script: referrerpolicy: origin-when-cross-origin

  20. html element: script: referrerpolicy: unsafe-url

  21. html element: script: src

  22. html element: script: type

  23. html element: script: type: `type="importmap"`

  24. html element: script: type: `type="importmap"`: integrity

  25. html element: script: type: `type="importmap"`: multiple import maps

  26. html element: script: type: `type="module"`

  27. html element: script: type: `type="speculationrules"`

  28. html element: script: type: `type="speculationrules"`: `eagerness` key

  29. html element: script: type: `type="speculationrules"`: `expects_no_vary_search` key

  30. html element: script: type: `type="speculationrules"`: `prefetch` key

  31. html element: script: type: `type="speculationrules"`: `prerender` key

  32. html element: script: type: `type="speculationrules"`: `referrer_policy` key

  33. html element: script: type: `type="speculationrules"`: `relative_to` key

  34. html element: script: type: `type="speculationrules"`: `requires` key

  35. html element: script: type: `type="speculationrules"`: `requires` key: `anonymous-client-ip-when-cross-origin` value

  36. html element: script: type: `type="speculationrules"`: `source` key is optional

  37. html element: script: type: `type="speculationrules"`: `tag` key

  38. html element: script: type: `type="speculationrules"`: `target_hint` key

  39. html element: script: type: `type="speculationrules"`: `urls` key

  40. html element: script: type: `type="speculationrules"`: `where` key

  41. javascript built-in: intl: locale: script

  42. svg element: script

  43. svg element: script: async

  44. svg element: script: defer

  45. svg element: script: fetchpriority

  46. svg element: script: href

  47. svg element: script: type

  48. svg element: script: type: `type='module'`

  49. svg element: script: xlink:href