Examine source code of Wikipedia Preview

{
  "manifest_version": 3,
  "version": "1.0.5",
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "wikipedia-search@viloris"
    }
  },
  "permissions": [
    "storage",
    "contextMenus"
  ],
  "options_ui": {
    "page": "options/index.html",
    "open_in_tab": true
  },
  "icons": {
    "32": "icons/32.png",
    "48": "icons/48.png",
    "64": "icons/64.png",
    "128": "icons/128.png",
    "512": "icons/512.png"
  },
  "background": {
    "scripts": [
      "background/background.js"
    ],
    "type": "module"
  },
  "action": {
    "default_icon": {
      "16": "icons/16.png",
      "19": "icons/19.png",
      "32": "icons/32.png",
      "38": "icons/38.png",
      "48": "icons/48.png",
      "64": "icons/64.png",
      "128": "icons/128.png",
      "512": "icons/512.png"
    },
    "default_popup": "popup/index.html"
  },
  "content_scripts": [
    {
      "all_frames": true,
      "match_about_blank": true,
      "matches": [
        "http://*/*",
        "https://*/*",
        "<all_urls>"
      ],
      "js": [
        "content/content.js"
      ],
      "css": [
        "content/content.css"
      ]
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "icons/512.png"
      ],
      "matches": [
        "*://*/*"
      ]
    }
  ],
  "commands": {
    "_execute_action": {
      "description": "__MSG_openPopupDescription__"
    },
    "wpSearchSelectedText": {
      "description": "__MSG_wikipediaSearchTextMenu__"
    }
  }
}