Examine source code of Dred+

{
  "manifest_version": 2,
  "name": "Dred+",
  "version": "1.2",
  "description": "Quality of Life improvemnts and enhancements for Dredark.",
  "icons": {
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/icon-96.png",
    "default_title": "Dred+",
    "default_popup": "index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "dredplus@example.com"
    }
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.drednot.io/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ]
}