Examine source code of News Category Selector

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "version": "1.0",
  "description": "__MSG_extensionDescription__",
  "icons": {
    "48": "icon.png"
  },
  "permissions": [
    "activeTab",
    "https://rss.nytimes.com/*"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "simplenewsfeeder5@example.com",
      "strict_min_version": "79.0"
    }
  }
}