Chat sessions disappear from history but remain in Chat Debug view; Export finds no data

Type: Bug

1. Work in a long-running Copilot Chat agent session in a WSL workspace
(session reached 147+ turns over multiple days).
2. Close or navigate away from the chat, or start a new chat session.
3. Return to the Chat History / Sessions panel to find the previous session.

Actual results:
- The session does not appear in the normal Chat Sessions panel/history list.
- Some sessions appear in the list with a malformed title
(e.g. "#attachment:Pasted text #1") instead of a normal auto-generated title,
and show 0 turns, making them unrecoverable through the UI even though the
Chat Debug view confirms the underlying session data still exists on disk
(visible with full tool-call traces, e.g. "hi the previce chat is not showin...",
"THE PRIVES CHAT IS NOT SHOW...", each with hundreds of logged tool calls).
- Clicking "Export Copilot Chat" from the status bar returns
"No Copilot data found" even though Chat Debug clearly shows extensive
session content exists.
- Reloading the window (Developer: Reload Window) does not restore the
missing sessions to the visible history.

Expected results:
- All completed chat sessions should remain visible and searchable in the
Chat History/Sessions panel, with correct titles and turn counts.
- The Export Copilot Chat feature should be able to retrieve and export
session data that is confirmed to exist in the Chat Debug view.

Impact: Loss of access to critical multi-day agent work session content
(147+ turns) with no way to recover it through any UI-exposed feature.

VS Code version: Code 1.134.0 (110a328ea54b42367b803ec53ee0bf52ef26b419, 2026-08-18T18:24:44Z)
OS version: Windows_NT x64 10.0.26200
Modes:
Remote OS version: Linux x64 6.18.33.2-microsoft-standard-WSL2

System Info

|Item|Value|
|---|---|
|CPUs|Intel(R) Core(TM) Ultra 9 185H (22 x 3072)|
|GPU Status|2d_canvas: enabled
GPU0: VENDOR= 0x8086, DEVICE=0x7d55 [Intel(R) Arc(TM) Graphics], DRIVER_VENDOR=Intel, DRIVER_VERSION=32.0.101.6127 *ACTIVE*
GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8972
Machine model name:
Machine model version:
direct_rendering_display_compositor: disabled_off_ok
gpu_compositing: enabled
multiple_raster_threads: enabled_on
opengl: enabled_on
rasterization: enabled
raw_draw: disabled_off_ok
skia_graphite: disabled_off
trees_in_viz: disabled_off
video_decode: enabled
video_encode: enabled
webgl: enabled
webgpu: enabled
webnn: disabled_off|
|Load (avg)|undefined|
|Memory (System)|31.37GB (10.51GB free)|
|Process Argv|--crash-reporter-id bd78da96-270f-4fbf-b312-b0bf2e375ad8|
|Screen Reader|no|
|VM|0%|

|Item|Value|
|---|---|
|Remote|WSL: Ubuntu|
|OS|Linux x64 6.18.33.2-microsoft-standard-WSL2|
|CPUs|Intel(R) Core(TM) Ultra 9 185H (22 x 0)|
|Memory (System)|15.30GB (10.38GB free)|
|VM|0%|
Extensions (15)

Name|Identifier|Author|Version
---|---|---|---
GitHub Copilot Chat Usage|ailmind.github-copilot-chat-usage|ailmind|0.7.0
Open in GitHub|fabiospampinato.vscode-open-in-github|fabiospampinato|2.4.0
GitHub Copilot Chat Exporter|fengzehan.vscode-copilot-exporter|fengzehan|0.1.1
GitHub Actions|github.vscode-github-actions|github|0.32.3
GitHub Pull Requests|github.vscode-pull-request-github|GitHub|0.162.0
GitHub Copilot for Azure|ms-azuretools.vscode-azure-github-copilot|ms-azuretools|1.0.231
Azure MCP Server|ms-azuretools.vscode-azure-mcp-server|ms-azuretools|2.0.46
Azure Resources|ms-azuretools.vscode-azureresourcegroups|ms-azuretools|0.12.7
Container Tools|ms-azuretools.vscode-containers|ms-azuretools|2.4.5
Codex – OpenAI’s coding agent|openai.chatgpt|openai|26.818.41705
Live Server|ritwickdey.liveserver|ritwickdey|5.7.10
GitHub Copilot modernization|vscjava.migrate-java-to-azure|vscjava|1.23.0
GitHub Copilot Chat RTL Support|yechielby.copilot-chat-rtl|yechielby|0.1.4
GitHub Codespaces|github.codespaces|GitHub|1.18.16
WSL|ms-vscode-remote.remote-wsl|ms-vscode-remote|0.104.3

A/B Experiments

```
vsliv368:30146709
pythonvspyt551cf:31249601
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
envsactivate1:31551504
cloudbuttont:31379625
3efgi100_wstrepl:31403338
ec5jj548:31422691
cp_cls_t_966_ss:31526232
4je02754:31466945
8hhj4413:31478653
ge8j1254_inline_auto_hint_haiku:31490510
cp_cls_c_1081:31454833
conptydll_true:31498968
e9c30283:31461165
test_treatment2:31471001
46204921:31447328
ei9d7968:31496641
nes-extended-on:31455476
chat:31457767
8hig5102:31480529
89g7j272:31518289
i2gc6536:31499202
52612955:31516516
ghj88844:31499326
ddid_t:31478206
hmra_i5g22:31518061
7df3h592:31512476
cp_cls_t_1082:31535311
logging_enabled_new:31498466
j0d79568:31499440
jb_cp_cls_t_632:31543129
56dj4588:31512888
32d76977:31512328
ha629193:31508444
jh5f2457_c:31540921
jbcp_cls_pctr_t:31531130
61138546:31518536
cp_intellij_t_nes:31548657
gf14b233:31526830
ahp-both-windows:31556933
sessions_5:31532894
hjji5903:31534458
f412h606:31551416
7g2b5551:31542111
enable_editor_pane_layout:31569726
allow-none:31555437
fd5dc207:31551400
36h42362:31564511
c7c27ce7:31554789
1h923230:31564177
1532g621_copy:31554320
treatment-23-1:31555779
unuse_dynamic_mcp:31555281
0d8dfbc3:31570291
a1hcc538:31559322
nemo-v2:31565334
0c1h4866:31566224
vrbsty_fls:31561059
session-mark-done:31558131
5b8j3302:31564601
mangle-name-treatment:31570928
permission_prompt_treatment:1332566
ccr_pr_nudge_auto_review:1319472
vsc_wsm_t:1340632

```