Examine source code of Reddit image viewer

{
  "manifest_version": 3,
  "name": "Reddit image viewer",
  "version": "1.0",
  "description": "Loads reddit images directly instead of referring to the HTML page containing the image.",
  "permissions": [
    "declarativeNetRequestWithHostAccess"
  ],
  "host_permissions": [
    "*://i.redd.it/*",
    "*://external-preview.redd.it/*",
    "*://preview.redd.it/*"
  ],
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "ruleset",
        "enabled": true,
        "path": "rules.json"
      }
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{17d08f04-db63-4926-a0e6-363aedb05a1c}"
    }
  }
}