New Features:
Added support for group tags (KDBX 4.1).
In the entry/group dialogs, there now is a button to show a menu for adding/removing existing tags.
If an entry/group inherits a tag from a parent group, a link is displayed in the entry/group dialog to show the parent groups and their tags.
Added option in the entry dialog for disabling/enabling the password quality estimation for the current entry (KDBX 4.1).
If the password quality estimation is disabled for an entry, the entry is now excluded from password quality reports (menu 'Find' → 'Password Quality').
When moving an entry/group into a different group (e.g. into the recycle bin), the previous parent group is remembered now (KDBX 4.1, not enforcing).