Gell all polygons from a rendered Leaflet map

get_leaflet_layers_polygons.js

// chrome snippet
var layersMarkers = [];
var layersPolygons = [];
var layers = []
var geojson = {
    "type": "FeatureCollection",
    "features": []
}
var output = {
    "type": "FeatureCollection",
    "features": []
}
map.eachLayer(function(layer) {
    layers.push(layer);
    if (layer instanceof L.Marker)
        layersMarkers.push(layer);
    if (layer instanceof L.Polygon)
        layersMarkers.push(layer);
    if (typeof layer.toGeoJSON === 'function')
        geojson.features.push(layer.toGeoJSON());

});

output.features = (geojson.features.filter(d=>d.geometry?.type === 'Polygon' && d.geometry?.coordinates[0][0]))

copy(output)