Examine source code of REHack

{
  "manifest_version": 2,
  "name": "REHack",
  "version": "1.0.4.2",
  "author": "TheAirBlow",
  "description": "Injects REHack v1.0.4",
  "permissions": [
    "<all_urls>",
    "tabs",
    "activeTab",
    "storage",
    "webNavigation"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "96": "icons/96.png",
    "128": "icons/128.png"
  }
}