Description of problem:
There is no icon showing in system tray under kde plasma even if you enable it in preferences.
The problem is that virt-manager uses AppIndicator3.IndicatorCategory.OTHER which is wrong(?). At least in spec under this value is written " ... please don’t use unless you really need it."
Maybe better category will be APPLICATION_STATUS.
The real reason is that there is a misalignment between indicator category enum definition in Appindicator3 and KNotifications but maybe thats reason for another bug.
Version-Release number of selected component (if applicable): 1.4.3
Thanks for the report, I fixed this a while ago but forgot to close it:
Author: Cole Robinson <crobinso>
Date: Wed Oct 18 18:50:42 2017 -0400
systray: Use APPLICATION_STATUS for appindicator
Not OTHER, as the reporter points out this shouldn't be used, and
causes issues on KDE