Examine source code of Container Session Proxy

{
  "manifest_version": 2,
  "name": "Container Session Proxy",
  "description": "Assigns a deterministic proxy session to each Firefox container.",
  "version": "0.1.0",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "48": "icon/48.png",
    "96": "icon/96.png",
    "128": "icon/128.png"
  },
  "permissions": [
    "cookies",
    "privacy",
    "proxy",
    "storage",
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "browser_action": {
    "default_title": "Container Session Proxy",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "browsingActivity",
          "websiteContent"
        ]
      },
      "id": "container-session-proxy@example.local",
      "strict_min_version": "142.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}