src/java.desktop/windows/classes/sun/awt/windows/WInputMethod.java

*** 587,596 ****
--- 587,599 ----
                  int x = 0;
                  int y = 0;
                  Component client = getClientComponent();
  
                  if (client != null) {
+                     if (!client.isShowing()) {
+                         return;
+                     }
                      if (haveActiveClient()) {
                              Rectangle rc = inputContext.getTextLocation(TextHitInfo.leading(0));
                              x = rc.x;
                              y = rc.y + rc.height;
                      } else {