let them go,
inxi -S
System: Host: hhl Kernel: 4.6.2-towo.1-siduction-amd64 x86_64 (64 bit) Desktop: KDE Plasma 5.6.4
Distro: siduction 15.1.0 Thunderstruck - kde - (201512041044)
#################################
LANG=C apt-cache policy kactivities
kactivities:
Installed: (none)
Candidate: (none)
Version table:
###################
LANG=C apt search kactivities
Sorting... Done
Full Text Search... Done
libkactivities-bin/unstable 4:4.13.3-1 amd64
executables for the KDE Activities
libkactivities-dbg/unstable 4:4.13.3-1 amd64
debugging symbols for libkactivities
libkactivities-dev/unstable 4:4.13.3-1 amd64
development files for the KDE Activities libraries
libkactivities-models1/unstable 4:4.13.3-1 amd64
Activities models library
libkactivities6/unstable,now 4:4.13.3-1 amd64 [installed]
Activities library
libkf5activities-dev/unstable 5.22.0-2 amd64
development files for kactivities.
libkf5activitiesstats-dev/unstable 5.22.0-2 amd64
development files for kactivities-stats.
libkf5activitiesstats1/unstable 5.22.0-2 amd64
usage data collected by the activities system
#########################################
LANG=C apt search lib kf screen
Sorting... Done
Full Text Search... Done
libkf5plotting-dev/unstable 5.22.0-1 amd64
development files for kplotting
libkf5plotting5/unstable 5.22.0-1 amd64
KPlotting provides classes to do plotting.
libkf5screen-bin/unstable,now 4:5.6.4-3 amd64 [installed,automatic]
library for screen management - helpers
libkf5screen-dev/unstable 4:5.6.4-3 amd64
library for screen management - development files
libkf5screen7/unstable,now 4:5.6.4-3 amd64 [installed,automatic]
library for screen management - shared library
mgltools-cadd/unstable 1.5.7~rc1+cvs.20140424-1 all
Computer Aided Drug Discovery (CADD) Pipeline
mgltools-webservices/unstable 1.5.7~rc1+cvs.20140424-1 all
webservices for components of autodocktools
texlive-latex-extra/unstable,now 2016.20160520-1 all [installed]
TeX Live: LaTeX additional packages
and libqt5xcbqpa5 is a transitional package, "apt-cache show" will tell you.
Look for the other ones, there are replacements, for sure.
greetings and good luck
One last word, do not wait to long with a dist-upgrade, because it can cause trouble!