File Copy Participants never finishes

[matkatmusic]

Issue Type: Bug

Copy one file from another directory into a workspace directory via drag-and-drop.
The File Copy Participants dialog appears and doesn't go away, and the File copy never completes. The only solution is to hit the [cancel] button, which allows the file copy to complete.

Extension version: 2.3.14
VS Code version: Code 1.57.1 (Universal) (507ce72a4466fbb27b715c3722558bb15afa9f48, 2021-06-17T13:28:32.912Z)
OS version: Darwin x64 19.6.0
Restricted Mode: No

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-10700K CPU @ 3.80GHz (16 x 3800)
GPU Status	2d_canvas: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled webgl: enabled webgl2: enabled
Load (avg)	2, 2, 2
Memory (System)	64.00GB (2.31GB free)
Process Argv	-psn_0_9439488 --crash-reporter-id b7b14ef3-b8f3-4bb9-997b-7df296b8766a
Screen Reader	no
VM	22%

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