Lightweight Alarm clock

{
    "update_url": "https:\/\/clients2.google.com\/service\/update2\/crx",
    "name": "Lightweight Alarm clock ",
    "version": "1.0.0",
    "description": "Alarm clock, countdown, interval timer",
    "manifest_version": 3,
    "author": "Roman",
    "permissions": [
        "alarms",
        "notifications"
    ],
    "background": {
        "service_worker": "background.js"
    },
    "action": {
        "default_popup": "index.html",
        "default_icon": "icon.png",
        "default_title": "Alarm clock"
    },
    "content_scripts": [
        {
            "matches": [
                "*:\/\/*.index.html\/*"
            ],
            "js": [
                "background.js"
            ]
        }
    ]
}