Examine source code of tubi-add-ranking

{
  "manifest_version": 2,
  "name": "tubi-add-ranking",
  "description": "an addon to add IMDB ranking to tubi",
  "version": "1.2",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/16.png",
      "24": "icons/24.png",
      "32": "icons/32.png",
      "48": "icons/48.png"
    }
  },
  "permissions": [
    "storage",
    "*://www.omdbapi.com/*",
    "*://*.duckduckgo.com/*",
    "activeTab",
    "contextMenus"
  ],
  "icons": {
    "16": "icons/16.png",
    "24": "icons/24.png",
    "32": "icons/32.png",
    "48": "icons/48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7bb23cd7-94ad-4ed6-82fd-6aed82dab75f}"
    }
  }
}