Get cursor position when a file is dropped in textarea in Chrome

When you drag a file from your OS filesystem over a textarea or text input, a cursor appears near the mouse pointer (this is different from positionStart), showing the user where the dragged content would be inserted.

UPDATE: here is an image, I'm dragging a file (test.sh) over the text input. You can see the drop cursor if the middle of the "text" word. The selection cursor is at the end of the string (not visible on this picture).

(Chrome's default behavior is to open the dropped file, but I'm overriding this behavior in the drop event. I want to insert the name of the file in the textarea.)

I'm trying to get this position (in terms of index in the textarea value string) when drop occurs. Any idea?

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