deprecated commands will be removed sooner or later, while it sometimes takes many years.
as first results it means we think there are much better ways to solve something and they should not used for new development and whenever existing code is touched, it should be considered to rewrite them.
For Drag&Drop, I believe so since v11, meaning more than 10 years.
The old commands required that sender & receiver are hard linked. it only works if both are connected.
If you want to add a 3rd element in that game, both existing ones needs to be rewritten.
As result, using the old concept, only a small group of objects supported drag&drop.
If you would consider to use the “new” (v11) approach, the same code would support drag&drop from listbox1 to listbox1, from listbox1 to listbox2 and even to Excel or other external applications.
Same window or other windows. Same process or other processes.
A very different way of thinking. For any object, write the “drag” code. The object only needs to know how to expose his data.
For any other, write the “drop” code. The object only needs to know how to receive data or respond to drops.
Following this concept opens very new possiblities…