[BUG] Tab toggle does not disable thinking mode / blue prompt lines stay on

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?

Tab no longer toggles thinking off in Claude Code. When thinking is globally enabled, pressing Tab shows the blue thinking indicator, but pressing Tab again no longer returns the prompt to the gray non‑thinking state. The blue lines stay on and thinking appears to remain enabled, consuming extra context/tokens. I can only reliably disable it by setting thinking to false in settings, which then prevents me from using thinking on demand

What Should Happen?

When I hit "Tab the thinking mode should turn on and off in Claude Code."

Error Messages/Logs

Steps to Reproduce

Just start Claude Code in the terminal, and you'll notice the blue lines are on all the time. When I hit tab, it doesn't work. The only way I can turn them off is if I go to /config and disable Thinking Mode from there.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.0.69

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_