Examine source code of Gitlab Easy Time Tracker

{
  "description": "A browser plugin for tracking time for GitLab merge-requests",
  "version": "0.6.3",
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "name": "Gitlab Easy Time Tracker",
  "short_name": "Time Tracker",
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "start-gray-16.png",
    "default_title": "Start tracking",
    "browser_style": true
  },
  "icons": {
    "16": "start-black-16.png",
    "48": "start-black-48.png",
    "96": "start-black-96.png",
    "128": "start-black-128.png"
  },
  "manifest_version": 2,
  "permissions": [
    "storage",
    "tabs"
  ],
  "applications": {
    "gecko": {
      "id": "{403d73be-461f-4ae9-9fa3-54f1b02498a2}"
    }
  }
}