When a HP network printer is selected as default printer in GNOME, the GTK+
print dialog in applications like Evince and Firefox very often hangs when
opened, showing "Getting printer information" for the printer.

Only after a delay of several seconds, the print button becomes active, and you
can proceed.

The problem does not happen, when no default printer is selected in the user
account in GNOME.

There is a work-around: comment the unix socket in /etc/cups/cupsd.conf and set
ServerName 127.0.0.1 in /etc/cups/client.conf

This launchpad bugs deals with the same problem on Ubuntu:
https://bugs.launchpad.net/ubuntu/+source/gtk+2.0/+bug/475845