Examine source code of AddB

{
  "manifest_version": 2,
  "name": "AddB",
  "version": "1.1",
  "description": "Adds a b to the end of every word on a page.",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "bbbb.js"
      ]
    }
  ]
}