Index: src/org/openstreetmap/josm/data/gpx/GpxConstants.java
===================================================================
--- src/org/openstreetmap/josm/data/gpx/GpxConstants.java	(revision 15558)
+++ src/org/openstreetmap/josm/data/gpx/GpxConstants.java	(working copy)
@@ -238,7 +238,7 @@
      */
     static Map<String, String> getExtensionAbbreviations() {
         TreeMap<String, String> m = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
-        m.put("gpx:extension:gpxx:TrackExtensions:DisplayColor", "gpxx:DisplayColor");
+        m.put("gpx:extension:gpxx:TrackExtension:DisplayColor", "gpxx:DisplayColor");
         m.put("gpx:extension:gpxd:color", "gpxd:color");
         return m;
     }
Index: src/org/openstreetmap/josm/data/gpx/GpxExtensionCollection.java
===================================================================
--- src/org/openstreetmap/josm/data/gpx/GpxExtensionCollection.java	(revision 15558)
+++ src/org/openstreetmap/josm/data/gpx/GpxExtensionCollection.java	(working copy)
@@ -147,7 +147,7 @@
 
     /**
      * Adds an extension from a flat chain without prefix, e.g. when converting from OSM
-     * @param chain the full key chain, e.g. ["extension", "gpxx", "TrackExtensions", "DisplayColor"]
+     * @param chain the full key chain, e.g. ["extension", "gpxx", "TrackExtension", "DisplayColor"]
      * @param value the value
      */
     public void addFlat(String[] chain, String value) {
Index: src/org/openstreetmap/josm/data/gpx/GpxTrack.java
===================================================================
--- src/org/openstreetmap/josm/data/gpx/GpxTrack.java	(revision 15558)
+++ src/org/openstreetmap/josm/data/gpx/GpxTrack.java	(working copy)
@@ -169,7 +169,7 @@
                     }
                 }
                 closestGarminColorCache.put(c, colorString);
-                getExtensions().addIfNotPresent("gpxx", "TrackExtensions").getExtensions().addOrUpdate("gpxx", "DisplayColor", colorString);
+                getExtensions().addIfNotPresent("gpxx", "TrackExtension").getExtensions().addOrUpdate("gpxx", "DisplayColor", colorString);
             } else if (cFormat == ColorFormat.GPXD) {
                 setColor(c);
             }
Index: src/org/openstreetmap/josm/gui/io/importexport/GpxImporter.java
===================================================================
--- src/org/openstreetmap/josm/gui/io/importexport/GpxImporter.java	(revision 15558)
+++ src/org/openstreetmap/josm/gui/io/importexport/GpxImporter.java	(working copy)
@@ -12,7 +12,10 @@
 import org.openstreetmap.josm.actions.ExtensionFileFilter;
 import org.openstreetmap.josm.data.gpx.GpxData;
 import org.openstreetmap.josm.gui.MainApplication;
+import org.openstreetmap.josm.gui.Notification;
 import org.openstreetmap.josm.gui.layer.GpxLayer;
+import org.openstreetmap.josm.gui.layer.ImageryLayer;
+import org.openstreetmap.josm.gui.layer.OsmDataLayer;
 import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
 import org.openstreetmap.josm.gui.progress.ProgressMonitor;
 import org.openstreetmap.josm.gui.util.GuiHelper;
@@ -153,6 +156,12 @@
                 gpxLayer.setLinkedMarkerLayer(markerLayer);
             }
         }
+
+        final boolean isSameColor = MainApplication.getLayerManager()
+                .getLayersOfType(ImageryLayer.class)
+                .stream().noneMatch(ImageryLayer::isVisible)
+                && data.getTracks().stream().anyMatch(t -> OsmDataLayer.getBackgroundColor().equals(t.getColor()));
+
         Runnable postLayerTask = () -> {
             if (!parsedProperly) {
                 String msg;
@@ -165,6 +174,13 @@
                 }
                 JOptionPane.showMessageDialog(null, msg);
             }
+            if (isSameColor) {
+                new Notification(tr("The imported track \"{0}\" might not be visible because it has the same color as the background." +
+                        "<br>You can change this in the context menu of the imported layer.", gpxLayerName))
+                .setIcon(JOptionPane.WARNING_MESSAGE)
+                .setDuration(Notification.TIME_LONG)
+                .show();
+            }
         };
         return new GpxImporterData(gpxLayer, markerLayer, postLayerTask);
     }
Index: test/data/tracks/tracks-extensions.gpx
===================================================================
--- test/data/tracks/tracks-extensions.gpx	(revision 15558)
+++ test/data/tracks/tracks-extensions.gpx	(working copy)
@@ -17,9 +17,9 @@
   <trk>
     <extensions>
       <test:tag>Track extension</test:tag>
-      <gpxx:TrackExtensions>
+      <gpxx:TrackExtension>
         <gpxx:DisplayColor>Red</gpxx:DisplayColor>
-      </gpxx:TrackExtensions>
+      </gpxx:TrackExtension>
     </extensions>
     <trkseg>
       <extensions>
Index: test/unit/org/openstreetmap/josm/data/gpx/GpxTrackTest.java
===================================================================
--- test/unit/org/openstreetmap/josm/data/gpx/GpxTrackTest.java	(revision 15558)
+++ test/unit/org/openstreetmap/josm/data/gpx/GpxTrackTest.java	(working copy)
@@ -47,7 +47,7 @@
         ext.remove("gpxd", "color");
         trk.invalidate();
         assertNull(trk.getColor());
-        ext.add("gpxx", "TrackExtensions").getExtensions().add("gpxx", "DisplayColor", "Blue");
+        ext.add("gpxx", "TrackExtension").getExtensions().add("gpxx", "DisplayColor", "Blue");
         trk.invalidate();
         assertEquals(trk.getColor(), Color.BLUE);
         trk.setColor(null);
Index: test/unit/org/openstreetmap/josm/io/GpxWriterTest.java
===================================================================
--- test/unit/org/openstreetmap/josm/io/GpxWriterTest.java	(revision 15558)
+++ test/unit/org/openstreetmap/josm/io/GpxWriterTest.java	(working copy)
@@ -190,9 +190,9 @@
                 "  </metadata>\n" +
                 "  <trk>\n" +
                 "    <extensions>\n" +
-                "      <gpxx:TrackExtensions>\n" +
+                "      <gpxx:TrackExtension>\n" +
                 "        <gpxx:DisplayColor>Red</gpxx:DisplayColor>\n" +
-                "      </gpxx:TrackExtensions>\n" +
+                "      </gpxx:TrackExtension>\n" +
                 "    </extensions>\n" +
                 "    <trkseg>\n" +
                 "      <extensions>\n" +
@@ -262,9 +262,9 @@
                 "  </metadata>\n" +
                 "  <trk>\n" +
                 "    <extensions>\n" +
-                "      <gpxx:TrackExtensions>\n" +
+                "      <gpxx:TrackExtension>\n" +
                 "        <gpxx:DisplayColor>Red</gpxx:DisplayColor>\n" +
-                "      </gpxx:TrackExtensions>\n" +
+                "      </gpxx:TrackExtension>\n" +
                 "    </extensions>\n" +
                 "    <trkseg>\n" +
                 "      <extensions>\n" +