[BUG] Claude Code for Windows (Desktop): extraKnownMarketplaces from managed settings not applied to plugin registry

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?

Description:
When distributing a custom plugin via managed settings (claude.ai/admin-settings), Claude Code for Windows (Desktop App) reads the remote-settings.json correctly but fails to register the marketplace in the local plugin registry (known-marketplaces.json and the plugins directory).

Affected platform: Claude Code for Windows (Desktop App only)

Actual behavior:
The remote-settings.json is updated correctly, but the downstream initialization step (marketplace registration, plugin directory setup) is not executed by the Desktop App on Windows.

Workaround:
Running /plugin marketplace add once in the Claude Code CLI (Windows Terminal) on the same machine registers the marketplace. After that, Claude Code for Windows also picks it up correctly.

Works correctly on:
Claude Code CLI on Windows (Windows Terminal)
Claude Code on macOS

Environment:
OS: Windows (Enterprise, tested on Windows 11)
Claude Code Desktop App (Windows)
Plan: Team
Suspected root cause:

The Desktop App on Windows appears to skip the initialization step that processes extraKnownMarketplaces from managed/remote settings into the local plugin registry. The CLI executes this step on startup or sync; the Desktop App does not.

What Should Happen?

Expected behavior:
Claude Code for Windows reads extraKnownMarketplaces from the managed settings and automatically registers the marketplace (populates known-marketplaces.json, creates plugin directory structure), identical to the behavior of the CLI version.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:

1. Configure the following in claude.ai/admin-settings:

{
"extraKnownMarketplaces": {
"fischer": {
"autoUpdate": true,
"source": {
"source": "git",
"url": "<your-git-url>.git"
}
}
},
"forcedPlugins": {
"your-plugin@your-marketplace": true
}
}

1. Open Claude Code for Windows (Desktop App) on a Windows machine.
2. Verify that remote-settings.json in ~/.claude/ contains the managed settings — it does.
3. Check the plugins directory and known-marketplaces.json — the marketplace is not registered.

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

1.14271.0

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_