What happens looks consistent to a developer but a layman would consider this sureal.
- Drag from "preview" into main canvas and drop
- Modify sizes
I propose to make the preview non-draggable. I don't think this is intentional. In fact, when a token is copied from the main canvas, this preview is actually what is dropped. This drop on the main canvas may be intentional with copy and paste, but the drop from the preview is mostly accidental.
At least a one-step undo would be great here too.