Removed env vars from .env file don't leave the environment

[mgberg]

Type: Bug

Behaviour

I use the Python Environments extension to load environment variables from a .env file. I noticed today that if I REMOVE an environment variable from the file:

• The Python Environments extension DOES NOT want to trigger a relaunch of the terminal, and
• The removed variable will persist even after the terminal is relaunched and will exist in any new terminals launched.

I set some environment variables needed for testing some code, but now I can't remove them. The old environment variables no longer present in the .env file are still injected into the terminal even after trying the following:

• Reloading the window
• Restarting VSCode
• Restarting WSL and restarting VSCode

Steps to reproduce:

1. Add an env var to the .env file (e.g. FOO="bar") and save the .env file. The Python Environments extension should want to trigger a relaunch of the terminal.
2. Relaunch the terminal.
3. Check that the environment variable is set in the terminal (e.g. via export).
4. Change the value of the variable the .env file (e.g. FOO="BAR") and save the .env file. The Python Environments extension should want to trigger a relaunch of the terminal.
5. Relaunch the terminal.
6. Check that the environment variable is set in the terminal (e.g. via export).
7. Remove the environment variable from the .env file and save it. The Python Environments extension DOES NOT want to trigger a relaunch of the terminal.
8. Relaunch the terminal.
9. Verify that the removed environment variable is STILL SET in the terminal.

Diagnostic data

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

There is nothing output to the Python Output panel while performing the steps listed above.

Extension version: 2026.2.0
VS Code version: Code 1.109.4 (c3a26841a84f20dfe0850d0a5a9bd01da4f003ea, 2026-02-16T15:35:57.932Z)
OS version: Windows_NT x64 10.0.22631
Modes:
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2

• Python version (& distribution if applicable, e.g. Anaconda): 3.12.3.final.0
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): System
• Value of the python.languageServer setting: Default

User Settings

envFile: "<placeholder>"

languageServer: "Pylance"

testing
• pytestArgs: "<placeholder>"
• pytestEnabled: true

Installed Extensions

Extension Name	Extension Id	Version
debugpy	ms-	2025.18.0
hexeditor	ms-	1.11.1
insert-unicode	bru	0.15.1
isort	ms-	2025.0.0
java	red	1.52.0
js-debug	ms-	1.105.0
jupyter	ms-	2025.9.1
jupyter-renderers	ms-	1.3.0
live-server	ms-	0.4.17
parquet-viewer	dvi	3.0.1
python	ms-	2026.2.0
rainbow-csv	mec	3.24.1
roo-cline	Roo	3.49.0
ruff	cha	2026.36.0
shell-format	fox	7.2.8
vscode-data-preview	Ran	2.3.0
vscode-edit-csv	jan	0.11.8
vscode-gradle	vsc	3.17.2
vscode-graphql	Gra	0.13.2
vscode-java-debug	vsc	0.58.5
vscode-java-dependency	vsc	0.27.0
vscode-java-pack	vsc	0.30.5
vscode-java-test	vsc	0.44.0
vscode-js-profile-table	ms-	1.0.10
vscode-jupyter-cell-tags	ms-	0.1.9
vscode-jupyter-slideshow	ms-	0.1.6
vscode-langserver-shacl	sta	0.2.0
vscode-langserver-sms	sta	0.2.0
vscode-langserver-sparql	sta	0.2.1
vscode-langserver-trig	sta	0.2.0
vscode-langserver-turtle	sta	0.2.1
vscode-maven	vsc	0.45.1
vscode-pylance	ms-	2026.1.1
vscode-python-envs	ms-	1.16.0
vscode-sql-formatter	adp	1.4.4
vscode-stardog-languages	sta	0.1.0

System Info

Item	Value
CPUs	11th Gen Intel(R) Core(TM) i7-11850H @ 2.50GHz (16 x 2496)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x10de, DEVICE=0x24b7 [NVIDIA RTX A4000 Laptop GPU], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=31.0.15.2849 ACTIVE GPU1: VENDOR= 0x8086, DEVICE=0x9a60 [Intel(R) UHD Graphics], DRIVER_VERSION=31.0.101.4575 GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.22621.5415 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 webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.48GB (13.10GB free)
Process Argv	--crash-reporter-id d5bc46c6-7ee2-4441-a534-b51f433e46cc
Screen Reader	no
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	11th Gen Intel(R) Core(TM) i7-11850H @ 2.50GHz (16 x 0)
Memory (System)	15.36GB (12.50GB free)
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	11th Gen Intel(R) Core(TM) i7-11850H @ 2.50GHz (16 x 0)
Memory (System)	15.36GB (12.50GB free)
VM	0%

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notips:31457203
chat:31457767

[eleanorjboyd]

can you confirm the version of your python environments extension?

[mgberg]

@eleanorjboyd 1.16.0. Interesting that it didn't show up in the list of installed extensions inserted into the issue by vscode.

[eleanorjboyd]

Can you update to 1.20? We made updates that should fix this problem!

[mgberg]

That seems to have fixed the problem. Thanks!