Examine source code of school 21 avatar

{
  "manifest_version": 3,
  "name": "school 21 platform avatars",
  "version": "1.0.1",
  "description": "Добавляет аватары пользователей из Rocket.Chat на платформу School 21. Делает профили, соревнования и ленту активности более персонализированными. Расшинение не собирает данные.",
  "icons": {
    "32": "icons/32.png",
    "64": "icons/64.png",
    "128": "icons/128.png"
  },
  "author": "acup",
  "action": {
    "default_icon": {
      "32": "icons/32.png",
      "64": "icons/64.png",
      "128": "icons/128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://platform.21-school.ru/*"
      ],
      "world": "MAIN",
      "js": [
        "js/self_avatar.js"
      ],
      "run_at": "document_end"
    },
    {
      "matches": [
        "https://platform.21-school.ru/my-profile",
        "https://platform.21-school.ru/my-profile/*"
      ],
      "world": "MAIN",
      "js": [
        "js/my-profile.js"
      ],
      "run_at": "document_end"
    },
    {
      "matches": [
        "https://platform.21-school.ru/profile/*"
      ],
      "world": "MAIN",
      "js": [
        "js/profile.js"
      ],
      "run_at": "document_end"
    },
    {
      "matches": [
        "https://platform.21-school.ru/competition/*",
        "https://platform.21-school.ru/project/*/about"
      ],
      "world": "MAIN",
      "js": [
        "js/competition.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "school21avatar@acup.local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}