When using laptops or other systems that have a sleep or hibernate
functionality, it’s possible for long-running server connections to
become “hung”, requiring the user to manually close and re-open the
connections after the system resumes. On systems compiled with D-Bus
support (check the value of (featurep 'dbusbind)), Gnus can
register a D-Bus signal to automatically close all server connections
before the system goes to sleep. To enable this, set
gnus-dbus-close-on-sleep to a non-nil value.
For more information about D-Bus and Emacs, see D-Bus integration in Emacs.