{
  "babel": {
    "corejs": {
      "val": true,
      "note_id": "babel-core-js",
      "note_html": "This feature is supported when using Babel with <a href='https://github.com/zloirock/core-js'>core-js</a>."
    },
    "optional": {
      "val": "flagged",
      "note_id": "babel-optional-flag",
      "note_html": "This feature features requires an optional transformer setting."
    },
    "regenerator": {
      "val": true,
      "note_id": "babel-regenerator",
      "note_html": "This feature requires native generators or <code>regenerator-runtime</code>, it's a part of <code>babel-polyfill</code> or <code>babel-runtime</code>."
    }
  },
  "typescript": {
    "corejs": {
      "val": true,
      "note_id": "typescript-core-js",
      "note_html": "This feature is supported when using TypeScript with <a href='https://github.com/zloirock/core-js'>core-js</a>."
    },
    "fallthrough": {
      "val": "needs-polyfill-or-native",
      "note_id": "typescript-es6",
      "note_html": "TypeScript&apos;s compiler will accept code using this feature if the <code>--target ES6</code> flag is set, but passes it through unmodified and does not supply a runtime polyfill."
    },
    "downlevelIteration": {
      "val": true,
      "note_id": "typescript-downlevel-iteration",
      "note_html": "Requires the <code>downlevelIteration</code> compile option."
    },
    "notDownlevelIteration": {
      "val": false,
      "note_id": "typescript-not-downlevel-iteration",
      "note_html": "Does not work with the <code>downlevelIteration</code> compile option."
    }
  },
  "edge": {
    "experimental": {
      "val": "flagged",
      "note_id": "edge-experimental-flag",
      "note_html": "Flagged features have to be enabled via \"Enable experimental Javascript features\" setting under <code>about:flags</code>"
    }
  },
  "firefox": {
    "sharedmem": {
      "val": "flagged",
      "note_id": "firefox-sharedmem",
      "note_html": "The feature have to be enabled via <code>javascript.options.shared_memory</code> setting under <code>about:config</code>.  It is enabled by default in Firefox Developer Edition and Firefox Nightly builds."
    },
    "nomob": {
      "val": "flagged",
      "note_id": "firefox-nomob",
      "note_html": "The feature is available on desktop versions only, it is not available on mobile versions yet."
    },
    "developer": {
      "val": false,
      "note_id": "firefox-developer",
      "note_html": "The feature is available only in Firefox Developer Edition and Firefox Nightly builds."
    },
    "nightly": {
      "val": false,
      "note_id": "firefox-nightly",
      "note_html": "The feature is available only in Firefox Nightly builds."
    },
    "bigint": {
      "val": "flagged",
      "note_id": "firefox-bigint",
      "note_html": "The feature have to be enabled via <code>javascript.options.bigint</code> setting under <code>about:config</code>."
    },
    "classFields": {
      "val": "flagged",
      "note_id": "firefox-class-fields",
      "note_html": "The feature have to be enabled via <code>javascript.options.experimental.fields</code> setting under <code>about:config</code>."
    },
    "privateClassFields": {
      "val": false,
      "note_id": "firefox-private-class-fields",
      "note_html": "The feature have to be enabled via <code>javascript.options.experimental.fields</code> setting under <code>about:config</code>. Private fields are supported by parser, but behave as public fields."
    }
  },
  "chrome": {
    "sharedmem": {
      "val": "flagged",
      "note_id": "chrome-sharedmem",
      "note_html": "The feature have to be enabled via \"Experimental enabled SharedArrayBuffer support in JavaScript.\" setting under <code>about:flags</code>"
    },
    "experimental": {
      "val": "flagged",
      "note_id": "chrome-experimental",
      "note_html": "The feature have to be enabled via \"Experimental Javascript features\" setting under <code>about:flags</code>"
    },
    "harmony": {
      "val": "flagged",
      "note_id": "chrome-harmony",
      "note_html": "The feature have to be enabled via <code>--js-flags=\"--harmony\"</code> flag"
    },
    "tco": {
      "val": false,
      "note_id": "chrome-tco",
      "note_html": "The feature is considered unstable, but can be enabled via <code>--js-flags=\"--harmony-tailcalls\"</code> flag"
    },
    "promise": {
      "val": false,
      "note_id": "chrome-promise",
      "note_html": "The feature is considered unstable, but can be enabled via <code>--js-flags=\"--harmony-promise-finally\"</code> flag"
    },
    "simd": {
      "val": false,
      "note_id": "chrome-simd",
      "note_html": "The feature is considered unstable, but can be enabled via <code>--js-flags=\"--harmony-simd\"</code> flag"
    }
  },
  "sparseNote": {
    "val": true,
    "note_id": "sparse_arrays",
    "note_html": "Internet Explorer 6 - 8 do not differentiate between a dense array with undefined values, and a sparse array. Specifically, <code>`0 in [,]`</code> and <code>`0 in [undefined]`</code> both yield false - whereas in a compliant browser, the former would give `false`, the latter `true`. As such, ES5 array iteration methods can only be shimmed reliably when dealing with dense arrays."
  }
}