Examine source code of YourBoss

{
  "manifest_version": 3,
  "name": "YourBoss",
  "description": "YourBoss will block the sites based on your preference. If you open the sites on undesired time, it will immediately close the tab.",
  "version": "0.1.1",
  "icons": {
    "64": "icons/icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "my-extension-id@example.com"
    }
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "activeTab",
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background_script.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_script.js"
      ]
    }
  ],
  "action": {
    "default_icon": {
      "64": "icons/icon.png"
    },
    "default_popup": "browserAction/index.html",
    "default_title": "YourBoss"
  },
  "options_ui": {
    "page": "options/index.html"
  }
}