Windows 10 Windows 10 1903 can't copy files to shared folder root

[_Shorty]

For some reason 1903 isn't letting me move or copy files to the root folder of a share via Explorer. Although I can create a new folder in the root of a share, and put files in there, I cannot drag a file to the root in the left pane. It shows me the red crossed circle and I can't drop the file. I can right-click Copy the source and then go to the root of the shared folder and Paste and that copies the file just fine. But dragging and dropping it does not work.

LMB-drag to copy = red crossed circle

RMB-drag to move = red crossed circle

edit: However, dragging with LMB or RMB to a subfolder in the share works just fine. It is only the root giving me the red crossed circle.

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