Examine source code of PermaTab

{
  "name": "PermaTab",
  "version": "0.1.2",
  "description": "PermaTab Pinned Tabs become more useful by (1) Re-opening your pinned tabs when you open your browser (2) Re-opening pinned tabs immediately when you close them and (3) Deduplicating pinned tabs with the same URL.",
  "browser_specific_settings": {
    "gecko": {
      "id": "permatab@permatab.com"
    }
  },
  "manifest_version": 2,
  "background": {
    "page": "background/background.html",
    "persistent": true
  },
  "icons": {
    "48": "icons/icon48.png",
    "96": "icons/icon96.png"
  },
  "browser_action": {
    "default_icon": "icons/icon48.png",
    "default_title": "PermaTab",
    "default_popup": "popup/popup.html"
  },
  "permissions": [
    "tabs",
    "storage",
    "sessions"
  ]
}