Pull request #4048: KERNEL-7542 优化设计器发现的一些问题

Merge in DESIGN/design from ~HENRY.WANG/design:feature/10.0 to feature/10.0

* commit '345943696ffb6471ef6ce1126c2273bbb4e0feed':
  KERNEL-7542 优化设计器发现的一些问题

designer-base/src/main/java/com/fr/design/mainframe/EastRegionContainerPane.java

@@ -843,8 +843,10 @@ public class EastRegionContainerPane extends UIEastResizableContainer {
         }
 
         public void replaceContentPane(JComponent pane) {
-            contentArea.remove(this.contentPane);
-            contentArea.add(this.contentPane = pane);
+            if (pane != this.contentPane) {
+                contentArea.remove(this.contentPane);
+                contentArea.add(this.contentPane = pane);
+            }
             if (popupDialog != null && isPoppedOut) {
                 popupDialog.replaceContentPane(this);
             }