Examine source code of Anti-Grabify

{
  "name": "Anti-Grabify",
  "version": "1.18",
  "manifest_version": 2,
  "description": "Blocks IP grabbers from Grabify and other IP grabber links.",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "strict_min_version": "58.0",
      "id": "{68dfd413-aef7-4632-abb7-157a0387f1e7}"
    }
  },
  "icons": {
    "128": "icon_128.png"
  },
  "browser_action": {
    "default_icon": "icon_128.png",
    "default_title": "Anti-Grabify",
    "default_popup": "popup.html"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ]
}