Examine source code of Pornography Blocker

{
  "manifest_version": 2,
  "name": "Pornography Blocker",
  "version": "3.0",
  "description": "Blocks pornography websites and instead plays a video of Paul Washer talking about sexual sin.",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://*/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "web_accessible_resources": [
    "video.html",
    "Paul Washer - Whining About Sexual Sin.mp4",
    "websites.txt"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{a51ac787-bf7f-4d0f-8e1d-87c9926ee5e2}"
    }
  }
}