Plasma-nm has VLAN Support but it is not visible by default.
You have to enable "Show and configure virtual connections" in Network settings (right click on plasma-nm icon in panel.
You now have the option to add a vlan interface as a "virtual connection" (Connections editor).
Working in 4:5.11.4+p16.04+git20171223.0044-0, but i guess its present in previous versions also.
Plasma-nm has VLAN Support but it is not visible by default.
You have to enable "Show and configure virtual connections" in Network settings (right click on plasma-nm icon in panel.
You now have the option to add a vlan interface as a "virtual connection" (Connections editor).
Working in 4:5.11. 4+p16.04+ git20171223. 0044-0, but i guess its present in previous versions also.