I tried: gdebi-gtk /var/cache/apt/archives/phpmyadmin_4%3a3.4.10.1-1_all.deb without using sudo, and everything worked fine again, the debconf password questions were displayed.
So the bug is probably in software-center.
I tried: gdebi-gtk /var/cache/ apt/archives/ phpmyadmin_ 4%3a3.4. 10.1-1_ all.deb
without using sudo, and everything worked fine again, the debconf password questions were displayed.
So the bug is probably in software-center.