diff --git a/bundles/org.eclipse.e4.ui.workbench.addons.swt/src/org/eclipse/e4/ui/workbench/addons/cleanupaddon/CleanupAddon.java b/bundles/org.eclipse.e4.ui.workbench.addons.swt/src/org/eclipse/e4/ui/workbench/addons/cleanupaddon/CleanupAddon.java
index beb4e0f9dfee..c2fab02e0657 100644
--- a/bundles/org.eclipse.e4.ui.workbench.addons.swt/src/org/eclipse/e4/ui/workbench/addons/cleanupaddon/CleanupAddon.java
+++ b/bundles/org.eclipse.e4.ui.workbench.addons.swt/src/org/eclipse/e4/ui/workbench/addons/cleanupaddon/CleanupAddon.java
@@ -346,13 +346,16 @@ private void subscribeRenderingChanged(
 				int visCount = modelService.countRenderableChildren(container);
 
 				// Remove stacks with no visible children from the display (but not the
-				// model). Since event delivery is synchronous (EventBroker.send via
-				// EventAdmin.sendEvent and Display.syncExec), the visCount reflects
-				// the actual state at the time of this event and can be acted upon
-				// immediately without deferring via asyncExec.
-				if (visCount == 0 && !isLastEditorStack(container)) {
-					container.setToBeRendered(false);
-					transferPrimaryDataStackIfRemoved(container);
+				// model)
+				final MElementContainer<MUIElement> theContainer = container;
+				if (visCount == 0) {
+					Display.getCurrent().asyncExec(() -> {
+						int visCount1 = modelService.countRenderableChildren(theContainer);
+						if (!isLastEditorStack(theContainer) && visCount1 == 0) {
+							theContainer.setToBeRendered(false);
+							transferPrimaryDataStackIfRemoved(theContainer);
+						}
+					});
 				} else if (container.getParent() != null) { // omit detached windows
 					// if there are rendered elements but none are 'visible' we should
 					// make the container invisible as well
diff --git a/tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java b/tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
index d646a2150eef..3fa7f8b7679e 100644
--- a/tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
+++ b/tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
@@ -2445,6 +2445,9 @@ public void ensureCleanUpAddonCleansUp() {
 
 		assertTrue(partStackForPartBPartC.isToBeRendered(), " PartStack with children should be rendered");
 		partService.hidePart(partB);
+		// Drain pending events between hides so that the event queue is clean
+		// when the second hidePart queues CleanupAddon's asyncExec for visCount==0
+		contextRule.spinEventLoop();
 		partService.hidePart(partC);
 		contextRule.spinEventLoop();
 		assertFalse(partStackForPartBPartC.isToBeRendered(),