Examine source code of USACO Together

{
  "manifest_version": 3,
  "name": "USACO Together",
  "description": "An extension to track the progress of your friends on usaco.guide!",
  "version": "0.1.4",
  "icons": {
    "16": "assets/icon16.png",
    "32": "assets/icon32.png",
    "48": "assets/icon48.png",
    "128": "assets/icon128.png"
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "USACO Together"
  },
  "content_scripts": [
    {
      "js": [
        "content/content-script.js"
      ],
      "css": [
        "content/content-script.css"
      ],
      "matches": [
        "https://usaco.guide/*"
      ]
    }
  ],
  "externally_connectable": {
    "matches": [
      "https://usaco.guide/*"
    ]
  },
  "web_accessible_resources": [
    {
      "matches": [
        "https://usaco.guide/*"
      ],
      "resources": [
        "assets/*",
        "content/injected.js"
      ]
    }
  ],
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "jmlpdjciabnplpimhafibghkcpjckblh@usaco.oviyan.tech"
    }
  },
  "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAgccunvb8QvIg6zqTH78v2OIdPpUS6jYCX2i5W6vUNxu4jRTbl51zq7naK/lG9xOa7nDHXYT5vcKwR/IkgU3E86a+Rf5usBqm+37oZ2rnd0XMtbfaO31FktJ2PHX2MSyJI1+esD1KKgr6zEwoqTtAYJj7BC6LD8bYhlt5rbtZ5nyIxwUCT336w/AKWnRQkFbiN7BHc8dU402gnqRomCN7NEIX7MFyve7GCIHM3FSs3QPhGx4DznW6twJ5Egfe7ILNPHnUnFvPww26ag1m/QJn+29SBOZj68jnzEjhwB/nlxQygEshfq0G+Hp5Fj98DINajRypWO7eSdK1BQrH5d0spwIDAQAB"
}