Examine source code of Link Collector

{
  "manifest_version": 2,
  "name": "Link Collector",
  "version": "1.0",
  "description": "Collect and display all links from the current page",
  "icons": {
    "64": "icon64.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6255b202-0905-4a69-af48-491cf8f87f09}",
      "strict_min_version": "120.0"
    }
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "64": "icon64.png"
    }
  }
}