Examine source code of Save Windows

{
  "manifest_version": 2,
  "name": "Save Windows",
  "description": "Save all tabs in a window to check it later",
  "version": "1.0.3resigned1",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs",
    "http://*/*",
    "https://*/*"
  ],
  "browser_action": {
    "default_icon": "media/icon.png",
    "default_popup": "panel.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a280a599-e55c-42f3-8f6a-46a5ea9a874a}"
    }
  }
}