Ghosts of deleted entity files remain in RC ProjectManagement

Deleted entity files remain in ProjectManagement.
The files are deleted in Rapidclipse with "del". They are deleded from file system, but in Rapidclipse some of them remain in ProjectManagement listing as if they would still exist.

To reproduce:

• New RC project, import tables from the northwind sample database as entities.

• Open some of the entities with RC entity editor.

• (close all editors)

• delete all entities
  -> All entity *.java-Files are deleted from file system.
  

• But the entities previously opened with RC entity editor remains in ProjectManagement listing

See also images "DeleteNorthwindEntities3_RCX20201203_a.PNG" 'til "DeleteNorthwindEntities3_RCX20201203_d.PNG"

Additional remarks:

• The properties of the remainig "ghosts" can be opened (Contextmenu -> "Properties")

• They survive closing and reopening the project

• They seem not to survive a full RC restart