Examine source code of Faceit League Extension

{
  "manifest_version": 3,
  "name": "FaceitTeamExtension",
  "version": "1.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "{9b3683f7-5d11-4203-99e8-c46e4dc3b0c1}",
      "strict_min_version": "42.0"
    }
  },
  "description": "This is an extension for Faceit.com to see what team a player currently is competing on, designed to mimic how ESEA used to appear before the sites merged.",
  "action": {
    "default_popup": "popup.html",
    "default_title": "Faceit Team Displayer"
  },
  "background": {
    "scripts": [
      "Background.js"
    ]
  },
  "web_accessible_resources": [
    {
      "resources": [
        "Assets/Advanced.png",
        "Assets/Challenger.png",
        "Assets/Intermediate.png",
        "Assets/Main.png",
        "Assets/Open.png",
        "Assets/tile-large.png",
        "Assets/600px-ESEA_darkmode.png"
      ],
      "matches": [
        "https://www.faceit.com/*"
      ]
    }
  ],
  "host_permissions": [
    "https://www.faceit.com/*"
  ],
  "permissions": [
    "tabs",
    "scripting"
  ],
  "icons": {
    "48": "Assets/extension-logo48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.faceit.com/*"
      ],
      "js": [
        "TeamExtension.js"
      ]
    }
  ]
}