Examine source code of ZRedirect

{
  "name": "ZRedirect",
  "description": "Improve your killboard experience by redirecting external zkillboard.com links to kb.evetools.org!",
  "version": "1.1.0",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://zkillboard.com/*"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_start"
    }
  ],
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://zkillboard.com/kill/*"
  ]
}