1. CSS Feature Queries

    CSS Feature Queries allow authors to condition rules based on whether particular property declarations are supported in CSS using the @supports at rule.

  2. CSS if() function

    The `if()` CSS function allows different values to be set for a property depending on the result of a conditional test. The test can be based on a style query, a media query, or a feature query.

  3. CSS.supports() API

    The CSS.supports() static method returns a Boolean value indicating if the browser supports a given CSS feature, or not.

  4. clipboarditem api: `supports()` static method

  5. clipboard api: supports `image/png` mime type

  6. clipboard api: supports `text/html` mime type

  7. clipboard api: supports `text/plain` mime type

  8. cssimportrule api: supportstext

  9. csssupportsrule api

  10. css api: `supports()` static method

  11. css api: `supports()` static method: parentheses for single-argument version are optional.

  12. customelementregistry api: define: supports `disabledfeatures` static property

  13. domtokenlist api: supports

  14. htmlcanvaselement api: toblob: `type` parameter supports `"image/jpeg"`

  15. htmlcanvaselement api: toblob: `type` parameter supports `"image/png"`

  16. htmlcanvaselement api: toblob: `type` parameter supports `"image/webp"`

  17. htmlcanvaselement api: todataurl: `type` parameter supports `"image/jpeg"`

  18. htmlcanvaselement api: todataurl: `type` parameter supports `"image/png"`

  19. htmlcanvaselement api: todataurl: `type` parameter supports `"image/webp"`

  20. htmlscriptelement api: `supports()` static method

  21. idbdatabase api: transaction: `mode` parameter supports `readwriteflush`

  22. navigator api: registerprotocolhandler: `scheme` parameter supports `dat`

  23. navigator api: registerprotocolhandler: `scheme` parameter supports `did`

  24. navigator api: registerprotocolhandler: `scheme` parameter supports `ftp`

  25. navigator api: registerprotocolhandler: `scheme` parameter supports `geo`

  26. navigator api: registerprotocolhandler: `scheme` parameter supports `im`

  27. navigator api: registerprotocolhandler: `scheme` parameter supports `irc`

  28. navigator api: registerprotocolhandler: `scheme` parameter supports `mms`

  29. navigator api: registerprotocolhandler: `scheme` parameter supports `news`

  30. navigator api: registerprotocolhandler: `scheme` parameter supports `sip`

  31. navigator api: registerprotocolhandler: `scheme` parameter supports `sms`

  32. navigator api: registerprotocolhandler: `scheme` parameter supports `ssb`

  33. navigator api: registerprotocolhandler: `scheme` parameter supports `ssh`

  34. navigator api: registerprotocolhandler: `scheme` parameter supports `tel`

  35. navigator api: registerprotocolhandler: `scheme` parameter supports `urn`

  36. setinterval api: supports parameters for callback

  37. settimeout api: supports parameters for callback

  38. websocket api: supports protocol as specified by rfc 6455

  39. css at-rule: `@import`: `supports()` as import condition

  40. css at-rule: `@supports`: `font-format()`

  41. css at-rule: `@supports`: `font-tech()`

  42. css at-rule: `@supports`: `selector()`

  43. css selector: `::selection`: supports the `text-decoration` property

  44. types: `<image>`: `paint()`: supports additional parameters to pass to the `paintworklet`

  45. headers http header: supports-loading-mode

  46. headers http header: supports-loading-mode: `credentialed-prerender` directive

  47. headers http header: supports-loading-mode: `fenced-frame` directive

  48. svg element: path: d: `d` as css property supports `path()`