Examine source code of JSON Viewer+

{
  "manifest_version": 3,
  "name": "JSON Viewer",
  "description": "The most beautiful and customizable JSON/JSONP highlighter that your eyes have ever seen",
  "version": "0.19.7",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "128": "icon/128.png"
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "omnibox": {
    "keyword": "json-viewer"
  },
  "author": "rxliuli",
  "homepage_url": "https://github.com/rxliuli/json-viewer",
  "web_accessible_resources": [
    {
      "resources": [
        "assets/*",
        "themes/**/*"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "json-viewer@rxliuli.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "open_in_tab": true,
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_end",
      "js": [
        "content-scripts/content.js"
      ]
    }
  ]
}