Examine source code of Minguo year convertor

{
  "name": "Minguo year conventor",
  "manifest_version": 2,
  "version": "2.1resigned1",
  "author": "iigmir",
  "description": "Change Minguo/Gregorian year to Gregorian/Minguo year by select bar.",
  "icons": {
    "48": "icons/kmt.svg"
  },
  "permissions": [
    "activeTab",
    "storage",
    "browserSettings"
  ],
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "Minguo",
    "default_popup": "popup/year.html"
  },
  "options_ui": {
    "page": "settings/options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d8553748-98c2-4d1f-af8f-dc7008bace31}"
    }
  }
}