Examine source code of Dictionary Search

{
  "manifest_version": 2,
  "name": "Dictionary Search",
  "version": "1.1",
  "browser_specific_settings": {
    "gecko": {
      "id": "dictionary_search@perfectsecrecyapps.com"
    }
  },
  "description": "Searches selected text in preferred dictionary",
  "icons": {
    "48": "icons/globe-48.png",
    "96": "icons/globe-96.png"
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/globe-19.png",
      "38": "icons/globe-38.png"
    },
    "default_title": "Search selection"
  },
  "permissions": [
    "contextMenus",
    "activeTab",
    "storage"
  ],
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "background-script.js"
    ]
  },
  "commands": {
    "search-selection": {
      "suggested_key": {
        "default": "Alt+Z"
      },
      "description": "Search selection in dictionary"
    }
  },
  "options_ui": {
    "page": "options.html"
  },
  "homepage_url": "https://gitlab.com/y3g0r/search-dict-webext"
}