Examine source code of chrono

{
  "name": "chrono",
  "description": "Extend Firefox's history capabilities with browsing history stats, improved searching and additional features.",
  "applications": {
    "gecko": {
      "id": "{4f1f10c5-0ff4-4c63-bf59-c307c94dc552}",
      "strict_min_version": "54.0a1"
    }
  },
  "version": "1.1.2",
  "manifest_version": 2,
  "homepage_url": "https://github.com/sereneblue/chrono",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_title": "chrono",
    "default_area": "tabstrip",
    "default_icon": "icons/icon.svg"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "dashboard.html",
    "open_in_tab": true
  },
  "permissions": [
    "browsingData",
    "history",
    "storage",
    "tabs"
  ],
  "commands": {
    "openOptionsPage": {
      "suggested_key": {
        "default": "Ctrl+Alt+H"
      }
    }
  }
}