Custom actions in Submenu executed in current folder do use the wrong%d

Custom actions without Submenu work with current directory. But if their setting has Submenu, instead of the current directory they work in parent directory.

Version information

4.21.0git-f7c20143 (4.20 had the same issue)

Steps to reproduce

1. Create Custom action notify-send "$PWD".
2. Execute it on the current folder (nothing selected) and see it shows the current folder correctly.
3. Edit that Custom action, setting Submenu to Test
4. Execute it on the current folder (nothing selected) and see it shows the parent folder instead.

Current behavior

Any other ways to test, with %d etc., called by hotkey or context menu, all give the same result: it receives the parent dir instead of the current one.

Expected outcome

Work in the current folder, as when not in Submenu.