VSCode UI Freeze after Copilot Response

# Issue

Github Copilot issue with total vscode window freeze after some github copilot chats. During the event, the entire VS Code UI becomes unresponsive:
- Editor does not redraw.
- Mouse clicks are ignored or delayed.
- Process Explorer stops updating.
- Keyboard input is delayed.

A near full UI refresh happens and remains frozen for 30-120s. Occurs multiple times a day when using Copilot Chat heavily. Does not occur during normal editing or other VSCode activities

During freezes, VS Code itself typically remains below 10% CPU while etxproxy and/or plasmashell consume significant CPU resources. The UI eventually recovers without requiring VSCode to be restarted.

Selected Models Claude Opus 4.8, Claude Sonnet 5. Occurs in both ask and edit mode.

# Extensions
Disabling these extensions does not make a difference.
amiq.dvt@26.1.17
bitwisecook.tcl-lsp@2.2.0
ctippett.cmt_utils@1.0.0
geddski.macros@1.2.1
gruntfuggly.todo-tree@0.0.226

# VsCode Version
Currently using 1.135.0 but it has been an issue of varying degree since about version 1.118.0. Some releases are much better and then others get much worse.

Version: 1.135.0
Commit: 08d4889f9ec4a1685d257b9b95de036c8e1ce1e5
Date: 2026-08-25T14:26:52Z
Electron: 42.8.1
ElectronBuildId: 14906494
Chromium: 148.0.7778.280
Node.js: 24.18.1
V8: 14.8.178.38-electron.0
@github/copilot: 1.0.81-0
@github/copilot-sdk: 1.0.11
OS: Linux x64 4.18.0-477.27.1.el8_8.x86_64

# Hardware

Running vscode on an Linux ETX VDI

MODEL: VMware Virtual Platform
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
CPU: Intel(R) Xeon(R) Gold 6342 CPU @ 2.80GHz
Linux RELEASE: Red Hat Enterprise Linux release 8.8 (Ootpa)
KERNEL VERSION: 4.18.0-477.27.1.el8_8.x86_64
MEMORY: 65391036kB total, kB used, kB available
SWAP: 10485756kB total, 18948kB used, 10466808kB available

Vscode is run with the --disable-gpu option. Workspace has been limited to a single file server however vscode user settings are on a different file server. Tests do not seem to show this is the root cause.

# Troubleshooting

- Disabled GPU rendering (--disable-gpu)
- Disabled all nonessential extensions
- Single-file-server workspace configuration
- Restrictive files.watcherExclude
- Restrictive search.exclude
- Disabled explorer auto reveal
- Disabled explorer badges
- Terminal GPU acceleration off

None of the above materially changed the behavior.