Examine source code of Anchors reveal

{
  "name": "__MSG_extensionName__",
  "short_name": "Anchors Reveal",
  "description": "__MSG_extensionDescription__",
  "manifest_version": 3,
  "version": "1.4.1",
  "author": "Xavier “dascritch” Mouton-Dubosc",
  "homepage_url": "https://dascritch.net/post/2014/06/24/Sniffeur-d-ancre",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "jid1-XX0TcCGBa7GVGw@jetpack",
      "data_collection_permissions": {
        "required": [
          "websiteContent"
        ]
      }
    }
  },
  "permissions": [
    "activeTab",
    "scripting",
    "storage",
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "options_ui": {
    "page": "options.html"
  },
  "icons": {
    "16": "data/icon-16.png",
    "32": "data/icon-32.png",
    "64": "data/icon-64.png"
  },
  "action": {
    "default_area": "navbar",
    "default_icon": {
      "16": "data/icon-16.png",
      "32": "data/icon-32.png",
      "64": "data/icon-64.png"
    },
    "default_title": "__MSG_buttonDescription__"
  },
  "commands": {
    "_execute_action": {
      "suggested_key": {
        "default": "Alt+Shift+A"
      }
    }
  }
}