Folder opens in wrong VSC instance

Type: Bug

Open a VSC instance, open a workspace in it.
Open a 2nd VSV instance, open a folder in this VSC, it opens in the first VSC instance instead!

VS Code version: Code 1.129.0 (125df4672b8a6a34975303c6b0baa124e560a4f7, 2026-07-15T00:08:44Z)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

|Item|Value|
|---|---|
|CPUs|13th Gen Intel(R) Core(TM) i7-13620H (16 x 2918)|
|GPU Status|2d_canvas: enabled
GPU0: VENDOR= 0x10de, DEVICE=0x28a1 [NVIDIA GeForce RTX 4050 Laptop GPU], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=31.0.15.3652 *ACTIVE*
GPU1: VENDOR= 0x8086, DEVICE=0xa7a8 [Intel(R) UHD Graphics], DRIVER_VERSION=32.0.101.7082
GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8875
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)|15.71GB (3.97GB free)|
|Process Argv|--crash-reporter-id ca0350f4-96e7-4b6a-bd1f-a94ec5edb0f8|
|Screen Reader|no|
|VM|0%|
Extensions (13)

Name|Identifier|Author|Version
---|---|---|---
Project Manager|alefragnani.project-manager|alefragnani|13.1.0
gitignore|codezombiech.gitignore|codezombiech|0.10.0
Git History|donjayamanne.githistory|donjayamanne|0.6.20
GitLab|gitlab.gitlab-workflow|GitLab|6.85.3
Go|golang.go|golang|0.56.0
Python Debugger|ms-python.debugpy|ms-python|2026.6.0
Python|ms-python.python|ms-python|2026.4.0
Pylance|ms-python.vscode-pylance|ms-python|2026.2.1
Python Environments|ms-python.vscode-python-envs|ms-python|1.36.0
SFTP|natizyskunk.sftp|Natizyskunk|1.16.3
Codex – OpenAI’s coding agent|openai.chatgpt|openai|26.707.91948
vscode-pdf|tomoki1207.pdf|tomoki1207|1.2.2
Open in GitHub, Bitbucket, Gitlab, VisualStudio.com !|ziyasal.vscode-open-in-github|ziyasal|1.3.6

A/B Experiments

```
vsliv368cf:30146710
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
82j33506:31327384
6abeh943:31336334
envsactivate1:31551504
478i5457:31544283
cloudbuttont:31379625
3efgi100_wstrepl:31403338
55ia6109:31457054
ec5jj548:31422691
cp_cls_t_966_ss:31526232
4je02754:31466945
c3h7c220:31478652
38bie571_auto:31426784
cp_cls_c_1081:31454833
conptydll_true:31498968
e9c30283:31461165
test_treatment2:31471001
46204921:31447328
capico_bxe_098a3278:31551525
idci7584:31464702
e3e4d672:31494082
ei9d7968:31496641
chat:31457767
8hig5102:31480529
89g7j272:31518289
7e187181:31503455
i2gc6536:31499202
52612955:31516516
ghj88844:31499326
ddid_c:31478207
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
cdk-lw-on:31524445
f9bf7985:31543584
jh5f2457_c:31540921
41836166:31537719
jbcp_cls_pctr_t:31531130
61138546:31518536
cp_intellij_t_nes:31548657
d7b18187:31526828
nes-curr-leftover-1500:31538366
h561g132:31533256
sessions_5:31532894
ihg5j128:31534457
f412h606:31551416
7g2b5551:31542111
nes-ex-cf-euporie-03:31542868
fd5dc207:31551400

```