Examine source code of Discogs: Add All

{
  "manifest_version": 2,
  "name": "Discogs: Add All",
  "description": "Add all releases of a format to your Discogs wantlist",
  "version": "0.3.1",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.discogs.com/master/*",
        "*://www.discogs.com/label/*",
        "*://www.discogs.com/artist/*"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "https://api.discogs.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{7c585084-08d6-4ad2-8d70-74a2bb0675da}"
    }
  }
}