Undo does not reset the document saved state (Feature Request)

[tarun.johar]

The topic is already discussed at following Help on using FreeCAD forum link : viewtopic.php?f=3&t=58752&e=1&view=unread#unread

Undo does not reset the document saved state. The issue is reproducible with version 0.19 and 0.19.2

Steps to reproduce:

1. Create a new document
2. Create a Part Design box
3. Save the document
4. There is no '*' next to the document name
5. Create a Part Design cylinder
6. There is a '*' next to the document name
7. Select Edit | Undo

The cylinder disappears but there is still a '*' in the document tab.

We are developing a workbench that creates temporary objects for preview purposes. When an operation is canceled, the transaction is properly aborted but the document saved state is not reverted. Applications such as Emacs and LibreOffice keep track of the saved state as part of the undo stack, so this is a reasonable expectation for the user.