Comment # 23 on bug 1030829 from Michele Cherici

I've done more tests and the problem does not happens always.

Steps to replicate with Tumbleweed 20190219 snapshot:
- use plasma5-pk-updates without patch
https://build.opensuse.org/package/view_file/openSUSE:Factory/plasma5-pk-updates/0001-Hide-option-to-install-updates-on-Tumbleweed.patch?expand=1
- verify that the installed version of sddm package is 0.18.0-6.1 from OSS
repository (if the version is 0.18.0-8.1 than downgrade it)
- updater applet should show the available update for sddm package (0.18.0-8.1
from http://download.opensuse.org/update/tumbleweed/)
- do the update for sddm from the applet
- after the update the applet will show to you the available updates that
require a vendor change (it shows the same updates available with the command
zypper dup --allow-vendor-change)
- if you reboot, the updater applet shows no updates available (so it uses the
right solver now)

It seems that after the package update from Tumbleweed repository the applet
wrongly refresh the list of available updates and do not respect the
solver.dupAllowVendorChange = false config

Please let me know if someone else is able to replicate the problem.