Examine source code of Preferer

{
  "description": "Block clicking through on reddit. You can still read posts you find via a search engine. Checking messages is not blocked.",
  "manifest_version": 2,
  "name": "Preferer",
  "version": "2.0.3",
  "icons": {
    "48": "logo.svg",
    "96": "logo.svg"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://*.reddit.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "strict_min_version": "57.0a1",
      "id": "{9d30b08d-25a6-4674-a921-051e2f4c0f41}"
    }
  }
}