fix

packages/svelte/src/internal/client/reactivity/deriveds.js

@@ -112,7 +112,7 @@ let stack = [];
  * @param {Derived} derived
  * @returns {Effect | null}
  */
-export function get_derived_parent_effect(derived) {
+function get_derived_parent_effect(derived) {
 	var parent = derived.parent;
 	while (parent !== null) {
 		if ((parent.f & DERIVED) === 0) {

packages/svelte/src/internal/client/runtime.js

@@ -29,12 +29,7 @@ import {
 import { flush_tasks } from './dom/task.js';
 import { add_owner } from './dev/ownership.js';
 import { mutate, set, source } from './reactivity/sources.js';
-import {
+import { destroy_derived, execute_derived, update_derived } from './reactivity/deriveds.js';
-	destroy_derived,
-	execute_derived,
-	get_derived_parent_effect,
-	update_derived
-} from './reactivity/deriveds.js';
 import * as e from './errors.js';
 import { lifecycle_outside_component } from '../shared/errors.js';
 import { FILENAME } from '../../constants.js';
@@ -771,9 +766,14 @@ export function get(signal) {
 		}
 	} else if (is_derived && /** @type {Derived} */ (signal).deps === null) {
 		var derived = /** @type {Derived} */ (signal);
-		var parent_effect = get_derived_parent_effect(derived);
+		var parent = derived.parent;
 
-		if (parent_effect !== null && !parent_effect.deriveds?.includes(derived)) {
+		if (
+			parent !== null &&
+			(parent.f & DERIVED) === 0 &&
+			!(/** @type {Effect} */ (parent).deriveds?.includes(derived))
+		) {
+			var parent_effect = /** @type {Effect} */ (parent);
 			(parent_effect.deriveds ??= []).push(derived);
 		}
 	}