{
  "prefixes": {
    "feature": {
      "__compat": {
        "support": {
          "chrome": {
            "prefix": "-webkit-",
            "version_added": "10"
          },
          "firefox": [
            {
              "version_added": "12"
            },
            {
              "prefix": "-moz-",
              "version_added": "5"
            }
          ]
        }
      }
    }
  }
}