diff --git a/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowImpl.java b/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowImpl.java
index 3fe9b5884d44..970995492afc 100644
--- a/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowImpl.java
@@ -201,7 +201,7 @@ public final class ToolWindowImpl implements ToolWindowEx, Disposable {
 
   @Override
   public final boolean isVisible() {
-    return myToolWindowManager.isToolWindowVisible(myId);
+    return myToolWindowManager.isToolWindowRegistered(myId) && myToolWindowManager.isToolWindowVisible(myId);
   }
 
   @Override
diff --git a/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowManagerImpl.java
index 7953a2f3b4c0..052099a83d62 100644
--- a/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowManagerImpl.java
@@ -217,8 +217,10 @@ public class ToolWindowManagerImpl extends ToolWindowManagerEx implements Persis
       .handleFloating(toolWindowId -> {})
       .handleFocusLostOnPinned(toolWindowId -> {
         List<FinalizableCommand> commands = new ArrayList<>();
-        deactivateToolWindowImpl(getRegisteredInfoOrLogError(toolWindowId), true, commands);
-        execute(commands, true); // notify clients that toolwindow is deactivated
+        if (isToolWindowRegistered(toolWindowId)) {
+          deactivateToolWindowImpl(getRegisteredInfoOrLogError(toolWindowId), true, commands);
+          execute(commands, true); // notify clients that toolwindow is deactivated
+        }
       })
       .handleWindowed(toolWindowId -> {})
       .bind(myProject);