Warn Unsupported feature: html when use correct kml file

my cesium version:1.124.0,
vue version:2.7.16,
chrome version:131.0.6778.86,
how to import cesium(language:chinese):use cesium in vue2,
my code:mapShow.vue
kml file:<?xml version="1.0" encoding="UTF-8"?> <kml xmlns="http://www.opengis.net/kml/2.2"> <Document> <Folder> <name>Three Points Example</name> <Placemark> <name>Point 1</name> <Point> <coordinates>111.5349353282,30.6596247814,0</coordinates> </Point> </Placemark> <Placemark> <name>Point 2</name> <Point> <coordinates>111.5349548764,30.6595547427,0</coordinates> </Point> </Placemark> <Placemark> <name>Point 3</name> <Point> <coordinates>111.5349744246,30.6594847041,0</coordinates> </Point> </Placemark> </Folder> </Document> </kml>
my kml file can work in Sandcastle ,but when i run my code i get warnning:‘Unsupported feature: html’