Examine source code of Mail Capture

{
  "manifest_version": 2,
  "name": "Mail Capture",
  "version": "0.2.2resigned1",
  "description": "A helper for capturing things via email",
  "homepage_url": "https://github.com/huytd/mail-capture-extension",
  "background": {
    "persistent": false,
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "huytd189@gmail.com",
      "strict_min_version": "50.0"
    }
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "options_ui": {
    "page": "options.html"
  },
  "browser_action": {
    "default_icon": "mail-send.png"
  },
  "commands": {
    "_execute_browser_action": {
      "description": "Capture current page with Gmail",
      "suggested_key": {
        "default": "Ctrl+Shift+L",
        "mac": "Command+Shift+L"
      }
    }
  }
}