Examine source code of X Scroll Remember

{
  "manifest_version": 3,
  "id": "@x-scroll-remember",
  "name": "X Scroll Remember",
  "version": "1.1.0",
  "description": "Remembers which tweets you've seen in the Following feed on X (Twitter) and marks them with a green overlay",
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://x.com/*",
    "https://twitter.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://x.com/*",
        "https://twitter.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "icons": {
    "48": "icon48.png",
    "96": "icon96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@x-scroll-remember",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "id": "@x-scroll-remember",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}