Test steps:

Create a project and add view3D

Add other items (cube, sphere, cylinder, cone) to the scene by dragging and dropping them from the item library to the 3D Edit View

Choose any of the previously added item by clicking it in the navigator.

Copy and paste the item using keyboard shortcuts ctrl+c and ctrl+v or using the context menu.

->Copied item is created and seen in the navigator, but not visible in the 3D Edit View. Selection boxes and gizmos for the item are shown though. Restarting the 3D Edit View does not help.

Copy/paste of the cube model that is in the scene by default when view3D is added seems to work fine.