Error upgrading FC 21 to 23

edit

Following the instructions on the upgrade page, I get the following error:

dnf update --refresh
# goes fine
dnf install dnf-plugin-system-upgrade
# goes fine

dnf system-upgrade download --releasever=23
...
Running transaction check
Transaction check succeeded.
Running transaction test
Error: Transaction check error:
  file /usr/share/plasma/desktoptheme/default/widgets/notes.svgz conflicts between attempted installs of kdeplasma-addons-5.4.2-1.fc23.x86_64 and kf5-plasma-5.17.0-2.fc23.x86_64

What does this mean? What should I do? I appreciate any help.