fix(frontend): workaround storybook issue (#11334)

packages/frontend/src/components/global/MkAd.stories.impl.ts

@@ -4,6 +4,9 @@ import { userEvent, waitFor, within } from '@storybook/testing-library';
 import { StoryObj } from '@storybook/vue3';
 import MkAd from './MkAd.vue';
 import { i18n } from '@/i18n';
+
+let lock: Promise<undefined> | undefined;
+
 const common = {
 	render(args) {
 		return {
@@ -26,6 +29,16 @@ const common = {
 		};
 	},
 	async play({ canvasElement, args }) {
+		if (lock) {
+			console.warn('This test is unexpectedly running twice in parallel, fix it!');
+			console.warn('See also: https://github.com/misskey-dev/misskey/issues/11267');
+			await lock;
+		}
+
+		let resolve: (value?: any) => void;
+		lock = new Promise(r => resolve = r);
+
+		try {
 			const canvas = within(canvasElement);
 			const a = canvas.getByRole<HTMLAnchorElement>('link');
 			await expect(a.href).toMatch(/^https?:\/\/.*#test$/);
@@ -59,6 +72,10 @@ const common = {
 			await expect(aAgain).toBeInTheDocument();
 			const imgAgain = within(aAgain).getByRole('img');
 			await expect(imgAgain).toBeInTheDocument();
+		} finally {
+			resolve!();
+			lock = undefined;
+		}
 	},
 	args: {
 		prefer: [],