Tab Countdown Timer

{
    "update_url": "https:\/\/clients2.google.com\/service\/update2\/crx",
    "name": "Tab Countdown Timer",
    "version": "1.3.1",
    "manifest_version": 3,
    "description": "A Chromium Extension that allows you to set a timer that counts down and then closes the tab.",
    "icons": {
        "16": "icons\/hourglass16.png",
        "32": "icons\/hourglass32.png",
        "48": "icons\/hourglass48.png",
        "128": "icons\/hourglass128.png"
    },
    "action": {
        "default_popup": "popup\/popup.html"
    },
    "background": {
        "service_worker": "background\/background.js"
    },
    "permissions": [
        "alarms",
        "storage",
        "activeTab",
        "scripting"
    ],
    "content_security_policy": {
        "extension_pages": "script-src 'self'; object-src 'self'"
    }
}