Examine source code of WebChat

{
  "manifest_version": 2,
  "name": "WebChat",
  "description": "Chat with anyone on any website.",
  "version": "1.9.7",
  "icons": {
    "16": "logo.png",
    "32": "logo.png",
    "48": "logo.png",
    "128": "logo.png"
  },
  "permissions": [
    "storage",
    "notifications",
    "tabs"
  ],
  "homepage_url": "https://github.com/molvqingtai/WebChat",
  "browser_specific_settings": {
    "gecko": {
      "id": "molvqingtai@gmail.com"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "open_in_tab": true,
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*/*"
      ],
      "exclude_matches": [
        "*://*.csdn.com/*",
        "*://*.csdn.net/*",
        "*://127.0.0.1/*",
        "*://localhost/*"
      ],
      "run_at": "document_idle",
      "js": [
        "content-scripts/content.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "content-scripts/content.css"
  ],
  "browser_action": {}
}