Refactoring: small styling issues

Logic/FeatureSource/Sources/FeatureSourceMerger.ts

@@ -30,6 +30,9 @@ export default class FeatureSourceMerger implements IndexedFeatureSource {
     }
 
     public addSource(source: FeatureSource) {
+        if(!source){
+            return
+        }
         this._sources.push(source)
         source.features.addCallbackAndRun(() => {
             this.addData(this._sources.map((s) => s.features.data))

Logic/FeatureSource/TiledFeatureSource/DynamicGeoJsonTileSource.ts

@@ -71,7 +71,7 @@ export default class DynamicGeoJsonTileSource extends DynamicTileSource {
                     if (!isWhiteListed) {
                         console.debug(
                             "Not downloading tile",
-                            ...zxy,
+                                zxy,
                             "as it is not on the whitelist"
                         )
                         return undefined