Debugger fail to launch using python3.14

[Antares0982]

Type: Bug

Behaviour

Program exited immediately after launch. Log in console:

/usr/bin/env python /home/antares/.vscode/extensions/ms-pytho
n.debugpy-2025.10.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/launcher 40643 -- /....../....../test.py 
Traceback (most recent call last):
Traceback (most recent call last):
  File "/home/antares/.vscode/extensions/ms-python.debugpy-2025.10.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/_pydevd_sys_monitoring/_pydevd_sys_monitoring.py", line 876, in _unwind_event
    if not thread_info.trace or not thread_info.is_thread_alive():
  File "/home/antares/.vscode/extensions/ms-python.debugpy-2025.10.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/_pydevd_sys_monitoring/_pydevd_sys_monitoring.py", line 270, in is_thread_alive
    return not self.thread._handle.is_done()
AttributeError: '_MainThread' object has no attribute '_handle'

Steps to reproduce:

1. Start debugging any file with default config

Diagnostic data

launch.json configuration

{
            "name": "Python Debug: Current File",
            "type": "debugpy",
            "request": "launch",
            "program": "${file}",
            "console": "integratedTerminal",
            "cwd": "${workspaceFolder}",
        }

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

2025-10-10 23:51:39.840 [info] Send text to terminal:  /usr/bin/env /....../....../python /home/antares/.vscode/extensions/ms-python.debugpy-2025.10.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/launcher 40643 -- /....../....../test.py 

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

2025-10-10 23:57:35.999 [info] Resolving launch configuration with substituted variables
2025-10-10 23:57:36.001 [info] DAP Server launched with command: /....../....../python /home/antares/.vscode/extensions/ms-python.debugpy-2025.10.0-linux-x64/bundled/libs/debugpy/adapter
2025-10-10 23:57:36.079 [info] Received 'debugpySockets' event from debugpy.
2025-10-10 23:57:36.080 [info] Received 'debugpySockets' event from debugpy.
2025-10-10 23:57:36.080 [info] Received 'debugpySockets' event from debugpy.
2025-10-10 23:57:36.448 [info] Received 'debugpySockets' event from debugpy.
2025-10-10 23:57:37.395 [info] Received 'debugpySockets' event from debugpy.
2025-10-10 23:57:37.397 [info] Received 'debugpySockets' event from debugpy.

Extension version: 2025.14.0
VS Code version: Code 1.104.0 (f220831ea2d946c0dcb0f3eaa480eb435a2c1260, 2025-09-10T06:46:18.035Z)
OS version: Linux x64 6.16.5-zen1
Modes:

• Python version (& distribution if applicable, e.g. Anaconda): 3.13.7
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Unknown
  Details

System Info

Item	Value
CPUs	13th Gen Intel(R) Core(TM) i7-13700K (24 x 5299)
GPU Status	2d_canvas: unavailable_software direct_rendering_display_compositor: disabled_off_ok gpu_compositing: disabled_software multiple_raster_threads: enabled_on opengl: disabled_off rasterization: disabled_software raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: disabled_software video_encode: disabled_software vulkan: disabled_off webgl: unavailable_software webgl2: unavailable_software webgpu: disabled_off webnn: unavailable_software
Load (avg)	1, 1, 1
Memory (System)	31.11GB (22.74GB free)
Process Argv	--ozone-platform-hint=auto --enable-features=WaylandWindowDecorations --enable-wayland-ime=true --wayland-text-input-version=3 --enable-wayland-ime= /home/antares/ --crash-reporter-id 3d39dd49-44f2-4512-872f-495c7b4a2cf5
Screen Reader	no
VM	0%
DESKTOP_SESSION	plasma
XDG_CURRENT_DESKTOP	KDE
XDG_SESSION_DESKTOP	KDE
XDG_SESSION_TYPE	wayland

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[eleanorjboyd]

@rchiodo any ideas here?

[rchiodo]

That's the older version. You need the prerelease bits. We fixed debugpy 3.14 support in debugpy 1.8.16 I believe (which shipped with the latest prerelease version).

[Antares0982]

That's the older version. You need the prerelease bits. We fixed debugpy 3.14 support in debugpy 1.8.16 I believe (which shipped with the latest prerelease version).

My fault, it seems I didn't restart the plugins. The log says I was using 2025.10.0

/usr/bin/env python /home/antares/.vscode/extensions/ms-python.debugpy-2025.10.0-linux-x64/......