[BUG] Claude App Preview stopped supporting https!!!

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?

preview_start doesn't support HTTPS servers

The preview browser always connects via http:// regardless of the server's protocol. Servers that only accept HTTPS (e.g. with self-signed certs via mkcert) result in net::ERR_EMPTY_RESPONSE. There's no way to pass --ignore-certificate-errors or specify https:// as the connection URL via launch.json or the tool schema.

What Should Happen?

Expected: support a url field in launch.json (or similar) to let users specify the full URL including protocol.

Error Messages/Logs

Just see a blank screen.

Steps to Reproduce

Try to create a launch config for a local https server!

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.4758.0 (fb266c) 2026-04-24T20:22:30.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

_No response_