Examine source code of rustLink

{
  "name": "rustLink",
  "version": "1.0.1",
  "manifest_version": 2,
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "64": "icons/64.png",
    "128": "icons/128.png",
    "256": "icons/256.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://companion-rust.facepunch.com/*",
        "http://rustlink.io/*",
        "https://rustlink.io/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "permissions": []
}