Unmount not deferred components immediately

.changeset/cuddly-owls-smile.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: unmount not deferred components immediately

packages/svelte/src/internal/client/dom/blocks/svelte-component.js

@@ -51,7 +51,8 @@ export function component(node, get_component, render_fn) {
 
 		var defer = should_defer_append();
 
-		if (effect) {
+		// For sync context: immediately pause the old effect
+		if (!defer && effect) {
 			pause_effect(effect);
 			effect = null;
 		}