Examine source code of Base64 Decoder

{
  "manifest_version": 2,
  "name": "Base64 Decoder",
  "version": "1.7",
  "description": "Highlight and decode Base64 text instantly.",
  "icons": {
    "128": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Decode Base64"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "base64-decoder-plat@myself.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}