[BUG] v2.1.32 / Opus 4.6 regression: New tab unresponsive + EBUSY .claude.json lock

Description

Two issues with Claude Code v2.1.32 and new Opus 4.6 model (released morning of Feb 5, 2026):

Issue 1: New Tab Unresponsive on Startup

Opening a new tab, I can paste my usual startup commands but the window is completely unresponsive. Cannot type anything or start/resume a conversation. Eventually becomes responsive after unknown wait time.

Issue 2: EBUSY File Lock Error

After the tab became responsive and I started a new task:

ERROR  EBUSY: resource busy or locked, open 'C:\Users\Cassie\.claude.json'

at writeFileSync (unknown)
SQ (B:/~BUN/root/claude.exe:6192:1226)
eaI (B:/~BUN/root/claude.exe:6192:4188)
e$ (B:/~BUN/root/claude.exe:6192:2867)
...

Environment

• Broken: Claude Code v2.1.32, Opus 4.6 (new as of Feb 5 morning)
• Working: Claude Code v2.1.31, Opus 4.5 (older tabs still work fine)
• OS: Windows 10/11
• Shell: PowerShell

Regression Evidence

Older terminal windows running v2.1.31 with Opus 4.5 work perfectly fine. This is specific to the new v2.1.32 / Opus 4.6 update.

Related Issues

• #22970 - TUI freezes on Windows startup
• #23016 - Terminal freezes in 2.1.30/2.1.31
• #15079 - File locking on Windows (.claude.json)

This may be the same root cause as #22970/#23016 but manifesting in the newest release with the new model.