Thermal Monitor Plasmoid

Install

kpackagetool5 -t Plasma/Applet --install plasmoid

Preview without installing

plasmoidviewer --applet plasmoid  

Upgrade and restart Plasmashell

kpackagetool5 -t Plasma/Applet --upgrade plasmoid && killall plasmashell && kstart5 plasmashell

Plasma DataSource Engine Explorer

plasmaengineexplorer