[
  {
    "namespace": "manifest",
    "types": [
      {
        "$extend": "OptionalPermission",
        "choices": [
          {
            "type": "string",
            "enums": {
              "proxy": {
                "annotations": [
                  {
                    "version_added": "147"
                  }
                ]
              }
            }
          }
        ]
      }
    ]
  },
  {
    "namespace": "proxy",
    "annotations": [
      {
        "version_added": "147"
      }
    ],
    "properties": {
      "settings": {
        "annotations": [
          {
            "version_added": "false"
          },
          {
            "note": "Not supported in Thunderbird because it depends on private browsing functionality, which Thunderbird does not fully implement.",
            "bcd": true
          }
        ]
      }
    }
  }
]