Examine source code of Instant Booth Gallery

{
  "manifest_version": 3,
  "name": "Instant Booth Gallery",
  "version": "1.5",
  "browser_specific_settings": {
    "gecko": {
      "id": "{634c01f0-929c-4113-9e8a-1398776b5fe8}",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "description": "Loads every booth.pm gallery image up front and adds an instant zoomable viewer with a see-all grid. No more click-then-wait.",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://booth.pm/*",
    "https://*.booth.pm/*"
  ],
  "background": {
    "scripts": [
      "src/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://booth.pm/*/items/*",
        "https://booth.pm/items/*",
        "https://*.booth.pm/items/*"
      ],
      "js": [
        "src/content.js"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ],
  "action": {
    "default_title": "Instant Booth Gallery",
    "default_popup": "src/popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png"
    }
  }
}