Examine source code of LeetCode Canvas

{
  "manifest_version": 2,
  "name": "LeetCode Canvas",
  "version": "1.0",
  "description": "Add a drawing canvas to LeetCode problem pages",
  "content_scripts": [
    {
      "matches": [
        "*://leetcode.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon16.png",
      "128": "icons/icon16.png"
    },
    "default_title": "LeetCode Canvas"
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon16.png",
    "128": "icons/icon16.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c4f64bb1-1116-4b10-b41f-e10f1bd2926f}"
    }
  }
}