- Plesk Onyx for Linux
Email messages are not deleted in RoundCube: they are marked for deletion instead of being actually removed:
How to remove these emails to trash?
The option Flag the message for deletion instead of delete is enabled in RoundCube settings.
To disable this option:
In RoundCube go to Settings > Preferences > Server Settings.
Uncheck Flag the message for deletion instead of delete.
Save the changes.