Examine source code of Chronos

{
  "manifest_version": 2,
  "name": "Chronos",
  "version": "1.1.4resigned1",
  "author": "encadyma",
  "description": "A productive tab manager doubling as a website blocker. Let online work flow like time.",
  "applications": {
    "gecko": {
      "id": "chronos@encadyma.com",
      "strict_min_version": "57.0"
    }
  },
  "icons": {
    "48": "icons/icon.png"
  },
  "permissions": [
    "<all_urls>",
    "tabs",
    "storage",
    "unlimitedStorage",
    "topSites"
  ],
  "background": {
    "scripts": [
      "background/background.js",
      "main/main.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true,
    "browser_style": false
  },
  "browser_action": {
    "default_icon": "icons/tab_matds.png",
    "default_title": "Chronos",
    "default_popup": "popup/popup.html",
    "browser_style": false
  }
}