Index: trunk/src/org/openstreetmap/josm/data/imagery/vectortile/mapbox/Feature.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/imagery/vectortile/mapbox/Feature.java	(revision 17913)
+++ trunk/src/org/openstreetmap/josm/data/imagery/vectortile/mapbox/Feature.java	(revision 17914)
@@ -6,4 +6,5 @@
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 
 import org.openstreetmap.josm.data.osm.TagMap;
@@ -111,5 +112,5 @@
             if (value instanceof Double || value instanceof Float) {
                 // reset grouping if the instance is a singleton
-                final NumberFormat numberFormat = NumberFormat.getNumberInstance();
+                final NumberFormat numberFormat = NumberFormat.getNumberInstance(Locale.ROOT);
                 final boolean grouping = numberFormat.isGroupingUsed();
                 try {