  const nearestPointOnLine = turf.nearestPointOnLine(lineString, point);
            if (nearestPointOnLine.properties.dist < minDistance) {
                minDistance = nearestPointOnLine.properties.dist;
                closestLineString = lineString;
            }
        });
        return closestLineString;
    }

    var loadedTracks = new Set();

    var trackCache = new Map();


    async function fetchgeojson(trackid) {
        if (trackid === undefined) {
            console.log("Fetchgeojson: un