Yesterday I installed OpenSuse 15.1 (as an update from 42.3) and the update manager in the bottom right is saying I have 1512 updates (!!!) but is also saying “failed to activate service ‘org.freedesktop.PackageKit’ timed out” yet when I go into Yast and go to online update, it is showing no updates.
I am not sure, isn’t it configurable with right-click?
I haven’t installed (and tabood) PackageKit (which it use). I do not see it on my KDE, maybe because Package-Kit is not there. The aaplet itself is from plasm-5-pk-updates. You could deinstall that also, but as said, it seems not to be shown when PackageKit is not there.