diff --git a/src/main/java/qupath/ext/omero/core/apis/ApisHandler.java b/src/main/java/qupath/ext/omero/core/apis/ApisHandler.java
index eb7e88f..14fb50b 100644
--- a/src/main/java/qupath/ext/omero/core/apis/ApisHandler.java
+++ b/src/main/java/qupath/ext/omero/core/apis/ApisHandler.java
@@ -1,8 +1,10 @@
 package qupath.ext.omero.core.apis;
 
 import com.drew.lang.annotations.Nullable;
+import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.ReadOnlyBooleanProperty;
 import javafx.beans.property.ReadOnlyIntegerProperty;
+import javafx.beans.property.SimpleBooleanProperty;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import qupath.ext.omero.core.entities.annotations.AnnotationGroup;
@@ -25,7 +27,11 @@
 
 import java.awt.image.BufferedImage;
 import java.net.URI;
-import java.util.*;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutionException;
@@ -57,6 +63,7 @@ public class ApisHandler implements AutoCloseable {
     private final WebclientApi webclientApi;
     private final WebGatewayApi webGatewayApi;
     private final IViewerApi iViewerApi;
+    private final BooleanProperty areOrphanedImagesLoading = new SimpleBooleanProperty(false);
     private final Map<Long, BufferedImage> thumbnails = new ConcurrentHashMap<>();
     private final Map<Class<? extends RepositoryEntity>, BufferedImage> omeroIcons = new ConcurrentHashMap<>();
     private final boolean canSkipAuthentication;
@@ -300,14 +307,19 @@ public CompletableFuture<Integer> getNumberOfOrphanedImages() {
      *                  be possible to add elements to this list
      */
     public void populateOrphanedImagesIntoList(List<Image> children) {
-        getOrphanedImagesIds().thenAccept(orphanedImageIds -> jsonApi.populateOrphanedImagesIntoList(children, orphanedImageIds));
+        setOrphanedImagesLoading(true);
+
+        getOrphanedImagesIds()
+                .thenAcceptAsync(orphanedImageIds -> jsonApi.populateOrphanedImagesIntoList(children, orphanedImageIds))
+                .thenRun(() -> setOrphanedImagesLoading(false));
     }
 
     /**
-     * See {@link JsonApi#areOrphanedImagesLoading()}.
+     * @return whether orphaned images are currently being loaded.
+     * This property may be updated from any thread
      */
     public ReadOnlyBooleanProperty areOrphanedImagesLoading() {
-        return jsonApi.areOrphanedImagesLoading();
+        return areOrphanedImagesLoading;
     }
 
     /**
@@ -564,4 +576,8 @@ public CompletableFuture<Boolean> writeROIs(long id, Collection<Shape> shapes, b
     public CompletableFuture<Optional<ImageSettings>> getImageSettings(long imageId) {
         return iViewerApi.getImageSettings(imageId);
     }
+
+    private synchronized void setOrphanedImagesLoading(boolean orphanedImagesLoading) {
+        areOrphanedImagesLoading.set(orphanedImagesLoading);
+    }
 }
diff --git a/src/main/java/qupath/ext/omero/core/apis/JsonApi.java b/src/main/java/qupath/ext/omero/core/apis/JsonApi.java
index 8188c10..824086b 100644
--- a/src/main/java/qupath/ext/omero/core/apis/JsonApi.java
+++ b/src/main/java/qupath/ext/omero/core/apis/JsonApi.java
@@ -8,11 +8,8 @@
 import com.google.gson.JsonObject;
 import com.google.gson.JsonSyntaxException;
 import com.google.gson.reflect.TypeToken;
-import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.IntegerProperty;
-import javafx.beans.property.ReadOnlyBooleanProperty;
 import javafx.beans.property.ReadOnlyIntegerProperty;
-import javafx.beans.property.SimpleBooleanProperty;
 import javafx.beans.property.SimpleIntegerProperty;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -71,7 +68,6 @@ class JsonApi {
     private static final String WELLS_URL = "%s/api/v0/m/plateacquisitions/%d/wellsampleindex/%d/wells/";
     private static final String ROIS_URL = "%s/api/v0/m/rois/?image=%s";
     private final IntegerProperty numberOfEntitiesLoading = new SimpleIntegerProperty(0);
-    private final BooleanProperty areOrphanedImagesLoading = new SimpleBooleanProperty(false);
     private final IntegerProperty numberOfOrphanedImagesLoaded = new SimpleIntegerProperty(0);
     private final URI webURI;
     private final Map<String, String> urls;
@@ -398,7 +394,7 @@ public int getNumberOfOrphanedImages(List<Long> orphanedImagesIds) {
      * <p>
      *     Populate all orphaned images of this server to the list specified in parameter.
      *     This function populates and doesn't return a list because the number of images can
-     *     be large, so this operation can take tens of seconds.
+     *     be large, so this operation can take tens of seconds and should be run in a background thread.
      * </p>
      * <p>The list can be updated from any thread.</p>
      *
@@ -407,38 +403,25 @@ public int getNumberOfOrphanedImages(List<Long> orphanedImagesIds) {
      * @param orphanedImagesIds  the Ids of all orphaned images of the server
      */
     public void populateOrphanedImagesIntoList(List<Image> children, List<Long> orphanedImagesIds) {
-        setOrphanedImagesLoading(true);
         resetNumberOfOrphanedImagesLoaded();
 
         List<URI> orphanedImagesURIs = getOrphanedImagesURIs(orphanedImagesIds);
-        CompletableFuture.runAsync(() -> {
-            // The number of parallel requests is limited to 16
-            // to avoid too many concurrent streams
-            List<List<URI>> batches = Lists.partition(orphanedImagesURIs, 16);
-            for (List<URI> batch: batches) {
-                children.addAll(batch.stream()
-                        .map(this::requestImageInfo)
-                        .map(CompletableFuture::join)
-                        .flatMap(Optional::stream)
-                        .map(jsonObject -> ServerEntity.createFromJsonElement(jsonObject, webURI))
-                        .flatMap(Optional::stream)
-                        .map(serverEntity -> (Image) serverEntity)
-                        .toList()
-                );
-
-                addToNumberOfOrphanedImagesLoaded(batch.size());
-            }
-
-            setOrphanedImagesLoading(false);
-        });
-    }
+        // The number of parallel requests is limited to 16
+        // to avoid too many concurrent streams
+        List<List<URI>> batches = Lists.partition(orphanedImagesURIs, 16);
+        for (List<URI> batch: batches) {
+            children.addAll(batch.stream()
+                    .map(this::requestImageInfo)
+                    .map(CompletableFuture::join)
+                    .flatMap(Optional::stream)
+                    .map(jsonObject -> ServerEntity.createFromJsonElement(jsonObject, webURI))
+                    .flatMap(Optional::stream)
+                    .map(serverEntity -> (Image) serverEntity)
+                    .toList()
+            );
 
-    /**
-     * @return whether orphaned images are currently being loaded.
-     * This property may be updated from any thread
-     */
-    public ReadOnlyBooleanProperty areOrphanedImagesLoading() {
-        return areOrphanedImagesLoading;
+            addToNumberOfOrphanedImagesLoaded(batch.size());
+        }
     }
 
     /**
@@ -637,10 +620,6 @@ private static CompletableFuture<Optional<String>> getToken(Map<String, String>
         }
     }
 
-    private synchronized void setOrphanedImagesLoading(boolean orphanedImagesLoading) {
-        areOrphanedImagesLoading.set(orphanedImagesLoading);
-    }
-
     private List<URI> getOrphanedImagesURIs(List<Long> orphanedImagesIds) {
         return orphanedImagesIds.stream()
                 .map(id -> WebUtilities.createURI(urls.get(IMAGES_URL_KEY) + id))