fix

packages/svelte/src/internal/client/dom/blocks/await.js

@@ -4,6 +4,7 @@ import { remove } from '../reconciler.js';
 import {
 	current_block,
 	current_component_context,
+	flushSync,
 	set_current_component_context,
 	set_current_effect
 } from '../../runtime.js';
@@ -97,6 +98,8 @@ export function await_block(anchor_node, get_input, pending_fn, then_fn, catch_f
 				.then((value) => {
 					if (promise !== input) return;
 
+					flushSync(); // TODO this feels weird but is apparently necessary
+
 					if (pending_effect) {
 						pause_effect(pending_effect, () => {
 							// TODO make this unnecessary

packages/svelte/tests/runtime-legacy/samples/transition-js-await-block/_config.js

@@ -31,7 +31,6 @@ export default test({
 		fulfil(42);
 
 		return promise.then(() => {
-			flushSync();
 			raf.tick(80);
 			const ps = /** @type {NodeListOf<HTMLParagraphElement & { foo: number }>} */ (
 				target.querySelectorAll('p')