Examine source code of Pximg referer fixer

{
  "name": "Pximg referer",
  "version": "0.1.2resigned1",
  "description": "Pixiv's pximg site referer fixer.",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://*.pximg.net/"
  ],
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "{bae2fae3-e26b-40a1-9886-1864c9f4fed3}"
    }
  }
}