Updated threading for quest start game process.

src/main/java/forge/gui/home/quest/SubmenuQuestUtil.java

@@ -4,6 +4,8 @@ import java.io.File;
 import java.util.Set;
 
 import javax.swing.ImageIcon;
+import javax.swing.SwingUtilities;
+import javax.swing.SwingWorker;
 
 import net.miginfocom.swing.MigLayout;
 import forge.AllZone;
@@ -193,10 +195,17 @@ public class SubmenuQuestUtil {
         final QuestData qData = AllZone.getQuestData();
         final QuestEvent event = selectedOpponent.getEvent();
 
+        SwingUtilities.invokeLater(new Runnable() {
+            @Override
+            public void run() {
                 OverlayUtils.startGameOverlay();
                 OverlayUtils.showOverlay();
+            }
+        });
 
-        // Logic
+        final SwingWorker<Object, Void> worker = new SwingWorker<Object, Void>() {
+            @Override
+            public Object doInBackground() {
                 Constant.Runtime.HUMAN_DECK[0] = SubmenuQuestUtil.getCurrentDeck();
                 Constant.Runtime.COMPUTER_DECK[0] = event.getEventDeck();
                 Constant.Quest.OPP_ICON_NAME[0] = event.getIconFilename();
@@ -235,10 +244,16 @@ public class SubmenuQuestUtil {
                 else {
                     GameNew.newGame(SubmenuQuestUtil.getCurrentDeck(), event.getEventDeck());
                 }
+                return null;
+            }
 
-        // Start transisiton to match UI.
+            @Override
+            public void done() {
                 OverlayUtils.hideOverlay();
             }
+        };
+        worker.execute();
+    }
 
     /** Selectable panels for duels and challenges. */
     @SuppressWarnings("serial")