Examine source code of Seconded

{
  "manifest_version": 3,
  "name": "Seconded",
  "version": "1.0.2",
  "description": "Save the current page to your Seconded collection.",
  "permissions": [
    "activeTab",
    "storage",
    "contextMenus",
    "tabs"
  ],
  "host_permissions": [
    "https://getseconded.com/*",
    "https://securetoken.googleapis.com/*",
    "https://www.google-analytics.com/*"
  ],
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "https://getseconded.com/extension-signin*"
      ],
      "js": [
        "signin-content-script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'; base-uri 'self'"
  },
  "action": {
    "default_popup": "popup.html",
    "default_title": "Seconded",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "commands": {
    "save-current-page": {
      "suggested_key": {
        "default": "Ctrl+Shift+S",
        "mac": "Command+Shift+S"
      },
      "description": "Save current page to Seconded"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "seconded@getseconded.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "browsingActivity"
        ],
        "optional": [
          "websiteContent",
          "technicalAndInteraction"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}