Examine source code of Clear Bookmark Folder

{
  "author": "igorlogius",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "description": "add context menu to bookmark folder to remove all entries",
  "icons": {},
  "manifest_version": 2,
  "name": "clear-bookmark-folder",
  "permissions": [
    "menus",
    "bookmarks"
  ],
  "version": "1.0.2",
  "browser_specific_settings": {
    "gecko": {
      "id": "{c9cac8a6-c834-4a2d-9149-b8813b47713d}"
    }
  }
}