- Prevent a NPE when trying to zoom a card before a single card is selected.

forge-gui-desktop/src/main/java/forge/toolbox/special/CardZoomer.java

@@ -193,6 +193,10 @@ public enum CardZoomer {
     }
 
     private void displayCard() {
+        if (thisCard == null) {
+            return;
+        }
+
         isMouseWheelEnabled = false;
         setLayout();
         setImage();