Examine source code of Jisho Highlighter

{
  "manifest_version": 2,
  "name": "Jisho Highlighter",
  "version": "1.0",
  "description": "Highlight Japanese words on any webpage and get their meanings from Jisho.org.",
  "permissions": [
    "contextMenus",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0b08a79b-a5d3-48fe-b5f2-fb3f6c74074a}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}