Examine source code of GridTabs

{
  "manifest_version": 2,
  "name": "Tab Grid View",
  "version": "2.3.1",
  "description": "Safari-style fullscreen tab overview",
  "permissions": [
    "tabs",
    "activeTab",
    "storage",
    "unlimitedStorage",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_title": "Tab Grid View",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png"
    }
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+T"
      },
      "description": "Open Tab Grid View"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "96": "icons/icon96.png"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "browser_specific_settings": {
    "gecko": {
      "id": "{59e6a6b5-9aa3-41ca-96a8-ee7ada80a1f5}",
      "strict_min_version": "145.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}