Editor/tools/firefox-addon-sdk-1.16/test/addons/predefined-id-with-at/package.json

{
    "id": "predefined-id@test",
    "fullName": "predefined ID test",
    "author": "Erik Vold",
    "preferences": [{
        "name": "test",
        "type": "integer",
        "title": "test",
        "value": 5
    }]
}