Examine source code of Humble Helper

{
  "manifest_version": 3,
  "name": "Humble Helper",
  "version": "0.2.0",
  "description": "Tracks current Humble game bundles, marks Steam ownership and wishlists, and applies a preferred donation split.",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "humble-steam-filter@example.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "websiteContent"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "alarms",
    "storage"
  ],
  "host_permissions": [
    "https://*.humblebundle.com/*",
    "https://store.steampowered.com/*"
  ],
  "content_security_policy": {
    "extension_pages": "default-src 'self'; script-src 'self'; connect-src https://humblebundle.com https://*.humblebundle.com https://store.steampowered.com; img-src 'self' https://hb.imgix.net https://humblebundle-a.akamaihd.net; object-src 'none'; base-uri 'none'; frame-ancestors 'none'"
  },
  "background": {
    "scripts": [
      "shared.js",
      "background.js"
    ]
  },
  "action": {
    "default_title": "Humble Helper",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.humblebundle.com/games/*",
        "https://*.humblebundle.com/books/*",
        "https://*.humblebundle.com/software/*"
      ],
      "js": [
        "shared.js",
        "content/humble.js"
      ],
      "css": [
        "content/humble.css"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://*.humblebundle.com/games/*",
        "https://*.humblebundle.com/books/*",
        "https://*.humblebundle.com/software/*"
      ],
      "js": [
        "content/page-donation.js"
      ],
      "run_at": "document_idle",
      "world": "MAIN"
    }
  ]
}