I have looked but couldn't find anything. Is it possible to plot only specific layers of a KML. Specifically, I want to plot all polygons, but no placemarks.
I haven't tried this but you could loop through the featureInfos array and only process the Polygon type.
var kmlLayer = new KMLLayer( ... );
var featureInfos = kmlLayer.folders.featureInfos;
// Test if info.type == Polygon
// if it is a polygon do something with the feature - like add it to a graphics layer
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