You have opened a project. File > Revision control > Command group Modifications > Change tracking > Generate revision. In the Generate revision dialog, click [...] next to the Revision name field.
In this dialog, you can select an existing revision name.
Overview of the main dialog elements:
The revision names already present in the project are presented here in the table for selection.
Select a revision name and exit the dialog by clicking [OK]. The revision name and the associated comments are then entered into the Generate revision dialog where you can then edit them.
See also