Index: trunk/src/org/openstreetmap/josm/io/CachedFile.java
===================================================================
--- trunk/src/org/openstreetmap/josm/io/CachedFile.java	(revision 13727)
+++ trunk/src/org/openstreetmap/josm/io/CachedFile.java	(revision 13728)
@@ -13,5 +13,4 @@
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -490,5 +489,5 @@
                 uc = u.replaceAll("%<(.*)>", "");
             } else {
-                uc = u.replaceAll("%<(.*)>", "$1"+URLEncoder.encode(parameter, "UTF-8"));
+                uc = u.replaceAll("%<(.*)>", "$1" + Utils.encodeUrl(parameter));
             }
             if (!uc.equals(u))