Examine source code of Workona Tasks - Todo list & project manager

{
  "manifest_version": 2,
  "name": "Workona Tasks - Todo list & project manager",
  "short_name": "Workona Tasks",
  "version": "1.2.0",
  "minimum_chrome_version": "54",
  "description": "The best task list for work in the browser.",
  "homepage_url": "https://workona.com",
  "icons": {
    "16": "images/icon_16.png",
    "32": "images/icon_32.png",
    "48": "images/icon_48.png",
    "96": "images/icon_96.png",
    "128": "images/icon_128.png",
    "256": "images/icon_256.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "firefox-prod-tasks@firefox-workona.com"
    }
  },
  "permissions": [
    "tabs"
  ],
  "optional_permissions": [
    "history"
  ],
  "background": {
    "scripts": [
      "background.js",
      "runtime.js",
      "4.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": {
      "16": "images/icon_16.png",
      "32": "images/icon_32.png",
      "48": "images/icon_48.png",
      "96": "images/icon_96.png",
      "128": "images/icon_128.png",
      "256": "images/icon_256.png"
    },
    "default_title": "Workona Tasks",
    "default_popup": "popup.html"
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+Z"
      },
      "description": "Create a task in Workona"
    },
    "mytasks": {
      "suggested_key": {
        "default": "Alt+Shift+Z"
      },
      "description": "My Tasks"
    }
  },
  "content_scripts": [
    {
      "all_frames": true,
      "matches": [
        "https://workona.com/*"
      ],
      "js": [
        "messagePassing.js"
      ],
      "run_at": "document_start"
    }
  ]
}