Spawned Node child process hangs when starting parent with debugger

[filipmares]

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Issue Type: Bug

We have a main Electron Node process which we start with the debugger. It seems one of our child processes also gets the debugger attached and hangs when starting. This was repreoduced by verifying non-insider build doesn't hang.

VS Code version: Code - Insiders 1.45.0-insider (1c36d74, 2020-04-15T05:40:02.537Z)
OS version: Darwin x64 19.4.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-8850H CPU @ 2.60GHz (12 x 2600)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: disabled_off protected_video_decode: unavailable_off rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off_ok webgl: enabled webgl2: enabled
Load (avg)	3, 3, 2
Memory (System)	32.00GB (6.84GB free)
Process Argv
Screen Reader	no
VM	0%

Extensions (13)

Extension	Author (truncated)	Version
vscode-browser-preview	auc	0.6.6
color-info	bie	0.5.1
gitlens	eam	10.2.1
prettier-vscode	esb	4.4.0
vscode-test-explorer	hbe	2.18.0
rest-client	hum	0.23.2
vscode-docker	ms-	1.0.0
python	ms-	2020.3.71659
azure-account	ms-	0.8.9
vsliveshare	ms-	1.0.1947
debugger-for-chrome	msj	4.12.6
vscode-yaml	red	0.7.2
vscode-sort-package-json	uni	1.2.2

(2 theme extensions excluded)

[connor4312]

Do you have either of the settings debug.javascript.usePreview or debug.node.useV3 turned on to use our new debugger on Insiders?

[filipmares]

I do have one of those
"debug.javascript.usePreview": true,

Should I turn it off?

[connor4312]

Turning it off should fix the issue for you. I'll try to reproduce this tomorrow and, if successful, apply a fix to the preview debugger for tomorrow's nightly build.

[filipmares]

Thank you!

[connor4312]

@filipmares can you provide your launch config for debugging and share how you're spawning the child process? Trying to reproduce this using the electron-quick-start repo with a dummy child process and our sample launch.json works for me.

[filipmares]

Will DM on Teams. :)

[connor4312]

This is similar to #95128, I put a workaround for in microsoft/vscode-js-debug@6538f20 that should resolve it. Please let me know if you run into more issues.

/duplicate #95128