Fix MarkerSet disappearing when a POI-Marker is being removed

src/markers/HtmlMarker.js

@@ -45,7 +45,7 @@ export class HtmlMarker extends Marker {
         this.fadeDistanceMax = Number.MAX_VALUE;
 
         this.addEventListener( 'removed', () => {
-            if (this.element.parentNode) this.element.parentNode.removeChild(this.element);
+            if (this.element?.parentNode) this.element.parentNode.removeChild(this.element);
         });
 
         this.add(this.elementObject);

src/markers/MarkerSet.js

@@ -79,11 +79,11 @@ export class MarkerSet extends Scene {
         // add & update MarkerSets
         Object.keys(data).forEach(markerSetId => {
             if (updatedMarkerSets.has(markerSetId)) return;
+            updatedMarkerSets.add(markerSetId);
 
             let markerSetData = data[markerSetId];
             try {
                 this.updateMarkerSetFromData(markerSetId, markerSetData);
-                updatedMarkerSets.add(markerSetId);
             } catch (err) {
                 alert(this.events, err, "fine");
             }

src/util/Utils.js

@@ -129,7 +129,7 @@ export const alert = (element, message, level = "info") => {
     });
 
     // log alert to console
-    if (printToConsole) {
+    if (printToConsole !== false) {
         if (level === "info") {
             console.log(`[BlueMap/${level}]`, message);
         } else if (level === "warning") {