diff --git a/src/main/java/org/olat/ims/qti21/ui/editor/interactions/HotspotEditorController.java b/src/main/java/org/olat/ims/qti21/ui/editor/interactions/HotspotEditorController.java
index b8fdfd28381830f146eb58f3c0e0b4e4597dd083..c58fb62716f9804382547238d89b629ed8bb1e06 100644
--- a/src/main/java/org/olat/ims/qti21/ui/editor/interactions/HotspotEditorController.java
+++ b/src/main/java/org/olat/ims/qti21/ui/editor/interactions/HotspotEditorController.java
@@ -97,10 +97,11 @@ public class HotspotEditorController extends FormBasicController {
 	private RichTextElement textEl;
 	private FileElement backgroundEl;
 	private SingleSelection resizeEl;
+	private FormLink newRectButton;
+	private FormLink newCircleButton;
 	private SingleSelection cardinalityEl;
 	private FormLayoutContainer hotspotsCont;
 	private MultipleSelectionElement responsiveEl;
-	private FormLink newCircleButton, newRectButton;
 	private MultipleSelectionElement correctHotspotsEl;
 	private SingleSelection layoutEl;
 	private MultipleSelectionElement shadowEl;
@@ -303,7 +304,7 @@ public class HotspotEditorController extends FormBasicController {
 
 		correctHotspotsEl.clearError();
 		if(!restrictedEdit && !readOnly) {
-			if(correctHotspotsEl.getSelectedKeys().size() == 0) {
+			if(correctHotspotsEl.getSelectedKeys().isEmpty()) {
 				correctHotspotsEl.setErrorKey("error.need.correct.answer", null);
 				allOk &= false;
 			}
@@ -345,7 +346,7 @@ public class HotspotEditorController extends FormBasicController {
 			createHotspotChoice(Shape.RECT, "50,50,100,100");
 			updateHotspots(ureq);
 		} else if(backgroundEl == source) {
-			//upload in itemDirectory;
+			// upload in item directory;
 			if(FileElementEvent.DELETE.equals(event.getCommand())) {
 				if(backgroundEl.getUploadFile() != null && backgroundEl.getUploadFile() != backgroundEl.getInitialFile()) {
 					backgroundEl.reset();
@@ -570,6 +571,8 @@ public class HotspotEditorController extends FormBasicController {
 	}
 	
 	private void optimizeResizeEl(Size size, boolean selectSize) {
+		if(size == null) return;
+		
 		List<String> keys = new ArrayList<>();
 		List<String> values = new ArrayList<>();