Examine source code of Steam PricePerHour

{
  "manifest_version": 2,
  "name": "Steam PricePerHour",
  "version": "1.3.2",
  "description": "Smart value insights for Steam: shows price/hour ratio badges across search, home, sale pages, bundles, and individual game pages. Supports all Steam currencies.",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "steam-priceperhour@vintlgvard.com",
      "strict_min_version": "79.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "background": {
    "scripts": [
      "service_worker.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Steam PricePerHour",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "permissions": [
    "storage",
    "tabs",
    "https://store.steampowered.com/*",
    "https://steampowered.com/*",
    "https://howlongtobeat.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://store.steampowered.com/*",
        "https://steampowered.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_end"
    },
    {
      "matches": [
        "https://howlongtobeat.com/*"
      ],
      "js": [
        "spph_bridge.js"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ]
}