diff --git a/modules/layered_tile_map/editor/atlas_merging_dialog.cpp b/modules/layered_tile_map/editor/atlas_merging_dialog.cpp
index d45399ee6..8ff945b44 100644
--- a/modules/layered_tile_map/editor/atlas_merging_dialog.cpp
+++ b/modules/layered_tile_map/editor/atlas_merging_dialog.cpp
@@ -309,7 +309,7 @@ void AtlasMergingDialog::update_tile_set(Ref<LayeredTileSet> p_tile_set) {
 			if (texture.is_valid()) {
 				String item_text = vformat(TTR("%s (ID: %d)"), texture->get_path().get_file(), source_id);
 				atlas_merging_atlases_list->add_item(item_text, texture);
-				atlas_merging_atlases_list->set_item_metadata(-1, source_id);
+				atlas_merging_atlases_list->set_item_metadata(atlas_merging_atlases_list->get_item_count() - 1, source_id);
 			}
 		}
 	}
diff --git a/modules/layered_tile_map/editor/layered_tile_map_layer_editor.cpp b/modules/layered_tile_map/editor/layered_tile_map_layer_editor.cpp
index aa01983e7..1db985479 100644
--- a/modules/layered_tile_map/editor/layered_tile_map_layer_editor.cpp
+++ b/modules/layered_tile_map/editor/layered_tile_map_layer_editor.cpp
@@ -246,7 +246,7 @@ void LayeredTileMapLayerEditorTilesPlugin::_update_tile_set_sources_list() {
 		}
 
 		sources_list->add_item(item_text, texture);
-		sources_list->set_item_metadata(-1, source_id);
+		sources_list->set_item_metadata(sources_list->get_item_count() - 1, source_id);
 	}
 
 	if (sources_list->get_item_count() > 0) {
@@ -466,7 +466,7 @@ void LayeredTileMapLayerEditorTilesPlugin::_update_scenes_collection_view() {
 	}
 	if (scene_tiles_list->get_item_count() == 0) {
 		scene_tiles_list->add_item(TTR("The selected scene collection source has no scenes. Add scenes in the LayeredTileSet bottom tab."));
-		scene_tiles_list->set_item_disabled(-1, true);
+		scene_tiles_list->set_item_disabled(scene_tiles_list->get_item_count() - 1, true);
 	}
 
 	// Icon size update.
diff --git a/modules/layered_tile_map/editor/layered_tile_set_editor.cpp b/modules/layered_tile_map/editor/layered_tile_set_editor.cpp
index 11638b289..6a9736bea 100644
--- a/modules/layered_tile_map/editor/layered_tile_set_editor.cpp
+++ b/modules/layered_tile_map/editor/layered_tile_set_editor.cpp
@@ -220,7 +220,7 @@ void LayeredTileSetEditor::_update_sources_list(int force_selected_id) {
 		}
 
 		sources_list->add_item(item_text, texture);
-		sources_list->set_item_metadata(-1, source_id);
+		sources_list->set_item_metadata(sources_list->get_item_count() - 1, source_id);
 	}
 
 	// Set again the current selected item if needed.
diff --git a/modules/layered_tile_map/editor/layered_tile_set_scenes_collection_source_editor.cpp b/modules/layered_tile_map/editor/layered_tile_set_scenes_collection_source_editor.cpp
index a2f5d3572..cbcea42ff 100644
--- a/modules/layered_tile_map/editor/layered_tile_set_scenes_collection_source_editor.cpp
+++ b/modules/layered_tile_map/editor/layered_tile_set_scenes_collection_source_editor.cpp
@@ -351,7 +351,7 @@ void LayeredTileSetScenesCollectionSourceEditor::_update_scenes_list() {
 	}
 	if (scene_tiles_list->get_item_count() == 0) {
 		scene_tiles_list->add_item(TTR("Drag and drop scenes here or use the Add button."));
-		scene_tiles_list->set_item_disabled(-1, true);
+		scene_tiles_list->set_item_disabled(scene_tiles_list->get_item_count() - 1, true);
 	}
 
 	// Reselect if needed.