Paste Image into Background and Add Backdrop

[ASD]

What's the difference between "Paste Image into Background" and "Add Backdrop"?

Moreover, there is a problem that the added background can be deleted when the put background exists.

[LB]

Paste into background is just pixles on screen. They are erased when the screen scrolls away from them. Add backdrop makes a new backdrop object and it stays there until you choose to delete it with the "Delete created backdrop at (x,y)" action.

[ASD]

Thanks, LB.

Sorry, the problem above was wrong.
When the "added background exists", the "pasted background" can be deleted with the delete created backdrops action.

When only the pasted background exists, the background cannot be deleted.

Is this normal?