Missing confirmation dialog for folder-copy

Version information

• Thunar 4.20.6 (as well thunar 4.21.3)
• XFCE 4.20,
• Calculate Linux (Gentoo based).

Steps to reproduce

1. Open Thunar.
2. Run in the same directory:
   • mkdir -p t/d
   • mkdir d
3. Select d.
4. Copy d: press <Ctrl>+C.
5. Navigate into t.
6. Press <Ctrl>+V.

Current behavior

No dialog, the folders are merged without further notice

1. On cut, you see a dialog.
2. On copy, you don't see a dialog.

Expected outcome

1. Or presence of a dialog in both scenarios (the same dialog as for cut+paste should be shown: ).
2. Or absence of dialogs in both scenarios.