[BUG] VSCode extension: thinking blocks fail to render until reload

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?

VSCode Claude Code extension (Remote-SSH): When streaming thinking blocks, the thinking view will briefly flash before completely disappearing. Seems to be model-independent (Haiku, Sonnet[1m], Opus[1m]). Upon reloading the window, past thinking blocks will appear as normal (togglable).
Note that the CLI app doesn't seem to have any issues.

What Should Happen?

Thinking blocks shouldn't disappear.

Error Messages/Logs

Steps to Reproduce

1. Open VSCode with Claude Code Extension
2. Claude Code: Open in New Tab
3. Send prompt to a reasoning model: hey just checking thinking block rendering -- make a haiku in your CoT
4. Witness a flash of insight, pitiful in its lifespan, born only to be snuffed out by some rendering bug
5. See the model generate output as normal. FWIW my last test said "All set! Thinking blocks are rendering cleanly. What's next?" -- clearly a hallucination, YMMV
6. Developer: Reload Window
7. Check on the chat and the thinking blocks will have reappeared from the ether

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.29

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

Note: tested on macOS and Windows 11, both SSH'ing into a linux (ubuntu) box.

VSCode:
Version: 1.109.0 (system setup)
Commit: bdd88df003631aaa0bcbe057cb0a940b80a476fa
Date: 2026-02-04T02:01:38.288Z
Electron: 39.3.0
ElectronBuildId: 13168319
Chromium: 142.0.7444.265
Node.js: 22.21.1
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.22631

Extension:
Version: 2.1.38