[BUG] Claude Code web default domains not working

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

While using Claude Code web I'm unable to install various dependencies required to run my project.

I have a hooked configured for SessionStart that fails on:

#!/bin/bash
set -euox pipefail

curl -fsSL https://github.com/jdx/mise/releases/download/v2026.1.11/mise-v2026.1.11-linux-x64 -o /usr/local/bin/mise
chmod +x /usr/local/bin/mise

with

+ curl -fsSL https://github.com/jdx/mise/releases/download/v2026.1.11/mise-v2026.1.11-linux-x64 -o /usr/local/bin/mise
curl: (22) The requested URL returned error: 403

What Should Happen?

This documentation page clearly says that github.com is a _default_ allowed domain:
https://code.claude.com/docs/en/claude-code-on-the-web

It shouldn't 403. Makes using Claude Code web impossible for anything serious

<img width="526" height="298" alt="Image" src="https://github.com/user-attachments/assets/1eb20040-7985-42c8-b189-3cf37298ba5a" />

Error Messages/Logs

Steps to Reproduce

1. Add a SessionStart hook to your project that does any request to Github.
2. See it 403

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Web latest

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_