Integrated terminal drops first character of command when launched by extensions (Code Runner)

[Abhishekoppa]

Type: Bug

Description
When running code using an extension (Code Runner) in VS Code's integrated terminal,
the first character of the executed command is consistently missing.

Examples:

• "python -u file.py" becomes "ython -u file.py"
• "g++ file.cpp" becomes "++ file.cpp"

This only happens when the command is sent automatically to the integrated terminal.
Manual typing works correctly.

Steps to Reproduce

1. Open VS Code on Linux (Kali)
2. Install Code Runner extension
3. Enable "Run In Terminal"
4. Press Ctrl + Alt + N to run a Python or C++ file
5. Observe that the first character of the command is missing

Expected Behavior
The full command should be executed without losing characters.

Actual Behavior
The first character of the command is dropped intermittently.

Additional Notes

• Does not happen in external terminals
• Does not happen when typing commands manually
• Seems to be a race condition when focusing the integrated terminal
• Reproducible with multiple languages (Python, C++)
• Occurs on Linux using bash/zsh

Extension version: 0.12.2
VS Code version: Code 1.106.3 (bf9252a2fb45be6893dd8870c0bf37e2e1766d61, 2025-11-25T22:28:18.024Z)
OS version: Linux x64 6.12.38+kali-amd64
Modes:

System Info

Item	Value
CPUs	AMD Ryzen 5 7520U with Radeon Graphics (8 x 4203)
GPU Status	2d_canvas: enabled 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: disabled_software vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: disabled_off webnn: disabled_off
Load (avg)	1, 1, 1
Memory (System)	14.91GB (10.99GB free)
Process Argv	. --crash-reporter-id 42933162-7d6e-42b8-b243-1cdd227b4d0e
Screen Reader	no
VM	0%
DESKTOP_SESSION	lightdm-xsession
XDG_CURRENT_DESKTOP	XFCE
XDG_SESSION_DESKTOP	lightdm-xsession
XDG_SESSION_TYPE	x11

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