Index: /trunk/resources/data/validator/combinations.mapcss
===================================================================
--- /trunk/resources/data/validator/combinations.mapcss	(revision 18049)
+++ /trunk/resources/data/validator/combinations.mapcss	(revision 18050)
@@ -931,6 +931,4 @@
   group: tr("missing tag");
   set missing_piste_difficulty;
-  assertMatch:   "way piste:type=nordic (count(parent_tag("piste:difficulty")) == 0)";
-  assertNoMatch: "way piste:type=nordic (count(parent_tag("piste:difficulty")) == 1)";
   assertNoMatch: "way piste:type=nordic piste:difficulty=easy";
 }
@@ -940,6 +938,4 @@
   group: tr("missing tag");
   set missing_piste_difficulty_both;
-  assertMatch:   "way piste:type=nordic (count(parent_tag("piste:difficulty")) == 0)";
-  assertNoMatch: "way piste:type=nordic (count(parent_tag("piste:difficulty")) == 1)";
   assertNoMatch: "way piste:type=nordic piste:difficulty=easy";
 }
Index: /trunk/src/org/openstreetmap/josm/data/ImageData.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/ImageData.java	(revision 18049)
+++ /trunk/src/org/openstreetmap/josm/data/ImageData.java	(revision 18050)
@@ -317,5 +317,5 @@
      * @param img the {@link ImageEntry} to remove
      * @param fireUpdateEvent if {@code true}, notifies listeners of image update
-     * @since xxx
+     * @since 18049
      */
     public void removeImage(ImageEntry img, boolean fireUpdateEvent) {
Index: /trunk/src/org/openstreetmap/josm/data/osm/OsmUtils.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/osm/OsmUtils.java	(revision 18049)
+++ /trunk/src/org/openstreetmap/josm/data/osm/OsmUtils.java	(revision 18050)
@@ -169,5 +169,6 @@
                 : null;
         if (p == null) {
-            throw new IllegalArgumentException("Expecting n/node/w/way/r/relation/area, but got '" + x[0] + '\'');
+            throw new IllegalArgumentException(
+                    "Expecting n/node/w/way/r/relation/area, but got '" + x[0] + "' for assertion '" + assertion + '\'');
         }
         if (x.length > 1) {
Index: /trunk/test/unit/org/openstreetmap/josm/gui/layer/geoimage/WikimediaCommonsLoaderTest.java
===================================================================
--- /trunk/test/unit/org/openstreetmap/josm/gui/layer/geoimage/WikimediaCommonsLoaderTest.java	(revision 18049)
+++ /trunk/test/unit/org/openstreetmap/josm/gui/layer/geoimage/WikimediaCommonsLoaderTest.java	(revision 18050)
@@ -11,9 +11,12 @@
 import java.util.List;
 
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
 import org.openstreetmap.josm.data.Bounds;
 import org.openstreetmap.josm.testutils.annotations.BasicPreferences;
+import org.openstreetmap.josm.tools.Http1Client;
+import org.openstreetmap.josm.tools.HttpClient;
 
 import com.github.tomakehurst.wiremock.WireMockServer;
-import org.junit.jupiter.api.Test;
 
 /**
@@ -22,4 +25,10 @@
 @BasicPreferences
 class WikimediaCommonsLoaderTest {
+
+    @BeforeAll
+    static void beforeAll() {
+        HttpClient.setFactory(Http1Client::new);
+    }
+
     /**
      * Unit test of {@link WikimediaCommonsLoader}
@@ -45,6 +54,6 @@
     }
 
-    private WireMockServer mockHttp() {
-        String xml = "" +
+    private static WireMockServer mockHttp() {
+        String xml =
                 "<api batchcomplete=\"\">\n" +
                 "<query>\n" +
@@ -57,5 +66,5 @@
         final WireMockServer wireMock = new WireMockServer(options().dynamicPort());
         wireMock.stubFor(get(urlEqualTo("/w/api.php?format=xml&action=query&list=geosearch" +
-                "&gsnamespace=6&gslimit=500&gsprop=type|name&gsbbox=48.0|11.0|47.0|12.0"))
+                "&gsnamespace=6&gslimit=500&gsprop=type%7Cname&gsbbox=48.0%7C11.0%7C47.0%7C12.0"))
                 .willReturn(aResponse().withBody(xml)));
         return wireMock;
Index: /trunk/test/unit/org/openstreetmap/josm/tools/MediawikiTest.java
===================================================================
--- /trunk/test/unit/org/openstreetmap/josm/tools/MediawikiTest.java	(revision 18049)
+++ /trunk/test/unit/org/openstreetmap/josm/tools/MediawikiTest.java	(revision 18050)
@@ -34,6 +34,9 @@
         // See https://josm.openstreetmap.de/ticket/21126
         // Checks that URL can be converted to URI, needed for HTTP/2
+        // CHECKSTYLE.OFF: LineLength
         assertEquals(new URI("https://commons.wikimedia.org/w/api.php?format=xml&action=query&list=geosearch&gsnamespace=6&gslimit=500&gsprop=type%7Cname&gsbbox=48.8623665%7C2.3913497%7C48.8600879%7C2.3967605"),
-                new URL(Mediawiki.getGeoImagesUrl("https://commons.wikimedia.org/w/api.php", new Bounds(48.8600879, 2.3913497, 48.8623665, 2.3967605))).toURI());
+                new URL(Mediawiki.getGeoImagesUrl("https://commons.wikimedia.org/w/api.php",
+                        new Bounds(48.8600879, 2.3913497, 48.8623665, 2.3967605))).toURI());
+        // CHECKSTYLE.ON: LineLength
     }
 }