problem with tray icons in KDE

Recently I upgraded my system to Kubuntu LTS 16.04 and 
now workrave's systray icons don't work. Sometimes I 
don't see them (blank space) and sometimes I see them 
but clicking them does not work. Something bad happened 
in 16.04 or in KDE 5 in general... :(

-- 
    Roman V. Isaev    http://www.isaev.ru    Moscow, Russia

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