FreeDOS Edit hangs after pressing Escape in submenu

Alt-O opens the Options menu. Pressing escape here, or in any other menu, dismisses it as expected. But opening the Options->Tabs submenu and then pressing Escape while it's visible causes Edit to hang after the menu is dismissed.

This is the only submenu in the program, so I couldn't test it anywhere else. It may be an issue with Edit or DFlat+. I don't know of any other DFlat+ applications to confirm.