The recent upgrade did not deal with obsolete conffiles properly.
Please use the dpkg-maintscript-helper support provided by
dh_installdeb to remove these obsolete conffiles on upgrade.

https://www.debian.org/doc/debian-policy/ch-files.html#s-config-files
https://manpages.debian.org/man/1/dh_installdeb

This bug report brought to you by adequate:

https://bonedaddy.net/pabs3/log/2013/02/23/inadequate-software/

$ p=thermald ; adequate $p ; dpkg-query -W -f='${Conffiles}\n' $p | grep obsolete
thermald: obsolete-conffile /etc/thermald/thermal-conf.xml
thermald: obsolete-conffile /etc/init.d/thermald
thermald: obsolete-conffile /etc/dbus-1/system.d/org.freedesktop.thermald.conf
 /etc/thermald/thermal-conf.xml 44437e985216ab918a6d2362c8dd1905 obsolete
 /etc/init.d/thermald e977b21364e668ce76072606621d1a4b obsolete
 /etc/dbus-1/system.d/org.freedesktop.thermald.conf a66eb6bd22779a225b0c2c30a25e6f56 obsolete