Index: trunk/src/org/openstreetmap/josm/gui/dialogs/changeset/ChangesetCacheManager.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/changeset/ChangesetCacheManager.java	(revision 11590)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/changeset/ChangesetCacheManager.java	(revision 11593)
@@ -753,5 +753,5 @@
             if (task.isCanceled() || task.isFailed())
                 return;
-            setSelectedChangesets(task.getDownloadedData());
+            GuiHelper.runInEDT(() -> setSelectedChangesets(task.getDownloadedData()));
         });
     }