Renaming of an annotation group to another one that already exist

Scenario:

1. Open Sequence View for "murine.gb".
2. Select group in the Annotations Editor: "misc_feature".
3. Open "Edit Group" dialog.
   Expected result: there is a field with "misc_feature" value.
4. Modify the value to "CDS", press Enter.
   Current result: the dialog is closed, but the group is not renamed.

This happens because only one group with a particular name can exist. However, this behavior is not clear at all.

Probably, the dialog should have buttons as other similar dialogs: "Edit", "Cancel", "Help". And "Edit" button should be disabled when the input name is the same as one of the groups in the same document. However, additional hint should be provided somehow, for example, highlight the field in red color and show a hint nearby.