File list disappears with drag and drop to Mixed in Key

I saw this post,

However, I'm only seeing this with one application which is weird.

I can drag and drop to other applications and the issue does not happen.

It's only when I drag the list to Mixed In Key for processing.

Link: https://mixedinkey.com/

The list will disappear and I can will refresh after.

This is a question for the target application.
If that tells the source application that the data is moved and not copied, then the objects disappear from the source application.
See also:

The official answer and "still no bug" from the developer (for the example target application "Audacity"):

@djquartz
What happens if you press CTRL to drag & drop files to "Mixed in Key" as suggested here:

I'll give this a try and see what it does.

What I'm thinking is it's possible MIK creates temp versions of the files which cause the condition.

I can refresh the list and everything is normal again, I just found it weird that only dragging the list to that application does this.

All the other apps I use to process tracks don't cause this behaviour.

For instance I can drag to Serato DJ for track analysis. It could drag the list to MLT (Music Library Tool) for genre analysis and no issue.

It only happens when I drag to Mixed in Key.

I'll try using Ctrl to see what it does.

See also here:

It must be something MIK is doing because none of the applications where I drag the list from mp3tag to them cause the list to disappear in the mp3tag.

I'll do some testing and update this.