VS Code crashes with SIGILL after continuing a GitHub Copilot Chat conversation

- Copilot Chat Extension Version: Built into VS Code 1.137.0; no separate extension version is shown
- VS Code Version: 1.137.0, x64
- OS Version: Arch Linux x86_64, Linux 7.2.4-arch1-2, GNOME on Wayland
- Feature (e.g. agent/edit/ask mode): Agent mode, working with HTML and image files
- Selected model (e.g. GPT 4.1, Claude 3.7 Sonnet): GPT-5.6 Sol
- Logs: Attached `vscode-chat-crash-logs.tar.gz`

Additional hardware information:

- Hardware: HUAWEI CREF-XX, SKU C233
- CPU: 12th Gen Intel Core i9-12900H
- Memory: 16 GiB
- GPU: Intel Alder Lake-P GT2 / Iris Xe Graphics
- GPU driver: i915
- BIOS version: 1.25

The crash happens in a Chat conversation in the `rms` workspace. The
conversation starts with a request similar to:

> Change the image style to the reference image...

After entering:

> Continue

VS Code usually crashes while rendering or continuing the Chat response. The
attached screen recording shows the behavior.

Linux recorded multiple crashes of `/usr/share/code/code` with `SIGILL` around
the same time:

- 2026-09-15 09:58:50 CST
- 2026-09-15 10:02:46 CST
- 2026-09-15 10:07:32 CST
- 2026-09-15 10:09:27 CST
- 2026-09-15 10:11:32 CST
- 2026-09-15 10:14:04 CST

Several core dumps were approximately 1.3 GB. The normal renderer log does not
contain a useful JavaScript stack trace.

Steps to Reproduce:

1. Open the attached `rms` workspace reproduction files.
2. Open GitHub Copilot Chat.
3. Open the conversation whose prompt starts with `Change the image style to
the reference image...`.
4. Use Agent mode.
5. Enter `Continue`.
6. Wait for the response and the workspace HTML/image content to render.
7. VS Code crashes.

Expected behavior:

The Chat conversation should continue and render the response normally.

Actual behavior:

The entire VS Code process exits while the Chat response or Chat UI is being
rendered. This is not only a failure of the Chat view.

Attachments:

[rms-chat-reproduction-files.tar.gz](https://github.com/user-attachments/files/32220541/rms-chat-reproduction-files.tar.gz)
[vscode-chat-crash-logs.tar.gz](https://github.com/user-attachments/files/32220542/vscode-chat-crash-logs.tar.gz)

https://github.com/user-attachments/assets/3d685440-5d3e-4d60-a48a-717208c58981

The recording is approximately 49 seconds long, 3840x2160, WebM/VP8. The crash happens between 40s-49s.