The addition of LPG for tanks has an error in /opt/v*/gui/qml/tank sensor.js
I get an error: Unable to assign QString to QColor which comes from the definition:
{
name: qsTr("LPG"),
icon: "overview-lpg",
color: "#8e7cc3 "
},
Note the space at the end of the color value. Removing the space makes things work properly