Examine source code of たてがき

{
  "manifest_version": 2,
  "name": "たてがき",
  "version": "1.1resigned1",
  "description": "青空文庫を縦書きで読めます。 アイコンをクリックで他ページも縦書きに",
  "icons": {
    "32": "img/icon32.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "content_scripts": [
    {
      "all_frames": false,
      "run_at": "document_start",
      "js": [
        "js/contentscript.js"
      ],
      "matches": [
        "<all_urls>",
        "file:///*/*"
      ]
    }
  ],
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "tategaki_senna5150ando@gmail.com",
      "strict_min_version": "57.0"
    }
  },
  "options_ui": {
    "open_in_tab": true,
    "page": "options.html"
  },
  "browser_action": {
    "default_icon": "img/icon19.png",
    "default_title": "たてがき"
  },
  "web_accessible_resources": [
    "reader.html"
  ],
  "permissions": [
    "tabs",
    "contextMenus",
    "unlimitedStorage",
    "storage"
  ]
}