Examine source code of Timeneye widget

{
  "name": "Timeneye widget",
  "description": "Track your time directly from Firefox in all your favourite tools",
  "manifest_version": 2,
  "version": "11.11.17",
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "options_ui": {
    "page": "html/options.html",
    "open_in_tab": true
  },
  "web_accessible_resources": [
    "/images/*",
    "/fonts/*",
    "/css/*"
  ],
  "browser_action": {
    "default_icon": "images/icon.png",
    "default_popup": "html/popup.html",
    "default_title": "Start a Timeneye timer or save an entry on the fly"
  },
  "permissions": [
    "identity",
    "storage",
    "https://*.timeneye.com/*"
  ],
  "background": {
    "scripts": [
      "js/firebase.js",
      "js/platform.js",
      "js/appkg.js",
      "js/event.js"
    ]
  },
  "commands": {
    "_execute_action": {
      "suggested_key": {
        "default": "Alt+Shift+T"
      }
    }
  },
  "content_security_policy": "script-src 'self' https://www.gstatic.com/ https://*.firebaseio.com https://www.googleapis.com https://securetoken.googleapis.com https://identitytoolkit.googleapis.com https://apis.google.com;; object-src 'self'",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/platform.js",
        "js/appkg.js",
        "js/content.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{bcb1e569-53ab-4475-868f-42062864eaa9}",
      "strict_min_version": "58.0"
    }
  }
}