Since upgrade to Plasma 6 neither various plasmoids nor System Monitor application can see network interfaces / stats.
System Monitor has an error line saying "This page is missing some sensors and will not display correctly" and a "Fix..." button. If I press the button I am presented with a dialog titled Replace Missing Sensors with a list of network related items such as "network/(?!all).*/upload".
But I have no idea what to do there. -- Andriy Gapon