Examine source code of Session Alive

{
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "2.4",
  "manifest_version": 3,
  "homepage_url": "https://github.com/arunelias/session-alive",
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs",
    "notifications",
    "storage",
    "contextualIdentities"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "Session Alive",
    "default_icon": "assets/icon/icon.png"
  },
  "icons": {
    "16": "assets/icon/icon.svg",
    "32": "assets/icon/icon.svg",
    "48": "assets/icon/icon.svg",
    "64": "assets/icon/icon.svg",
    "128": "assets/icon/icon.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{15060491-2b35-49f4-9f01-f35b127bebcc}",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "128.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "inject/cs.css"
      ],
      "js": [
        "inject/cs.js"
      ]
    }
  ],
  "options_ui": {
    "browser_style": false,
    "open_in_tab": true,
    "page": "settings/settings.html?"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "beep.wav"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "default_locale": "en"
}