diff --git a/frontend/src/components/filter-builder/controls/boolean-filter.tsx b/frontend/src/components/filter-builder/controls/boolean-filter.tsx
index a8102aa2..ff158904 100644
--- a/frontend/src/components/filter-builder/controls/boolean-filter.tsx
+++ b/frontend/src/components/filter-builder/controls/boolean-filter.tsx
@@ -1,3 +1,4 @@
+import { useId } from 'react'
 import { Button } from '@/components/ui/button'
 import type { Filter, FilterControlProps } from '../types'
 import { Operators } from '../utils/operators'
@@ -7,6 +8,7 @@ type BooleanFilterProps = Pick<FilterControlProps, 'config' | 'onSubmit'>
 
 export function BooleanFilter({ config, onSubmit }: BooleanFilterProps) {
   const { propertyKey, propertyLabel } = config
+  const labelId = useId()
   const handleSubmit = (selectedValue: boolean) => {
     onSubmit({
       propertyKey,
@@ -18,8 +20,8 @@ export function BooleanFilter({ config, onSubmit }: BooleanFilterProps) {
   }
 
   return (
-    <div className="flex flex-col gap-2 w-full md:w-48 p-3">
-      <div className="text-sm font-medium mb-2">{propertyLabel}</div>
+    <div role="group" aria-labelledby={labelId} className="flex flex-col gap-2 w-full md:w-48 p-3">
+      <div id={labelId} className="text-sm font-medium mb-2 in-data-[slot=responsive-dialog]:sr-only">{propertyLabel}</div>
       <div className="flex gap-2">
         <Button
           variant="outline"
diff --git a/frontend/src/components/not-found.tsx b/frontend/src/components/not-found.tsx
new file mode 100644
index 00000000..650ad56d
--- /dev/null
+++ b/frontend/src/components/not-found.tsx
@@ -0,0 +1,16 @@
+import { Link } from 'react-aria-components'
+
+import { buttonVariants } from '@/components/ui/button-variants'
+
+export function NotFound() {
+  return (
+    <div className="mx-auto flex max-w-md flex-col items-center px-4 py-16 text-center">
+      <p className="text-sm font-medium text-muted-foreground">404</p>
+      <h1 className="mt-2 text-3xl font-bold tracking-tight">Page not found</h1>
+      <p className="mt-2 text-muted-foreground">No page exists at this address.</p>
+      <Link href="/" className={buttonVariants({ className: 'mt-6' })}>
+        Go to the home page
+      </Link>
+    </div>
+  )
+}
diff --git a/frontend/src/components/toaster.tsx b/frontend/src/components/toaster.tsx
index 184a17a5..9da6f566 100644
--- a/frontend/src/components/toaster.tsx
+++ b/frontend/src/components/toaster.tsx
@@ -42,24 +42,26 @@ const iconColors = {
  */
 export function Toaster() {
   // React Aria lists the newest toast first. flex-col-reverse keeps it nearest the bottom edge.
-  // Below 768px the region spans the screen, and a toast is at most 500px wide. pointer-events-none lets a click beside
-  // or between the toasts reach the page. Each toast takes pointer events again, so hover still pauses the timers.
+  // Below 768px the region is centered and at most 500px wide, the width of a toast, so its focus ring fits the toast.
+  // pointer-events-none lets a click beside or between the toasts reach the page. Each toast takes pointer events again,
+  // so hover still pauses the timers.
   // index.css moves the region to the top while a bottom sheet is open.
   return (
     <ToastRegion
       queue={toastQueue}
       data-slot="toast-region"
-      className="pointer-events-none fixed inset-x-4 bottom-4 z-[100] flex flex-col-reverse items-center gap-2 outline-none md:right-6 md:bottom-6 md:left-auto"
+      className="pointer-events-none fixed inset-x-4 bottom-4 z-[100] mx-auto flex max-w-[500px] flex-col-reverse items-center gap-2 rounded-lg outline-none focus-visible:ring-3 focus-visible:ring-ring/50 md:right-6 md:bottom-6 md:left-auto"
     >
       {({ toast }) => (
         <Toast
           toast={toast}
+          data-slot="toast"
           style={{ viewTransitionName: toast.key, viewTransitionClass: 'toast' } as CSSProperties}
           className={cn(
             'bg-card text-card-foreground border border-border',
             'shadow-lg rounded-lg px-4 py-3',
             'pointer-events-auto flex w-full max-w-[500px] items-start gap-3 md:min-w-[300px]',
-            'outline-none focus-visible:ring-2 focus-visible:ring-ring'
+            'outline-none focus-visible:border-ring focus-visible:ring-3 focus-visible:ring-ring/50'
           )}
         >
           <ToastContent className="flex items-start gap-3 flex-1 min-w-0">
diff --git a/frontend/src/components/ui/skeleton.tsx b/frontend/src/components/ui/skeleton.tsx
index 0118624f..f5403108 100644
--- a/frontend/src/components/ui/skeleton.tsx
+++ b/frontend/src/components/ui/skeleton.tsx
@@ -4,7 +4,7 @@ function Skeleton({ className, ...props }: React.ComponentProps<"div">) {
   return (
     <div
       data-slot="skeleton"
-      className={cn("animate-pulse rounded-md bg-muted", className)}
+      className={cn("motion-safe:animate-pulse rounded-md bg-muted", className)}
       {...props}
     />
   )
diff --git a/frontend/src/index.css b/frontend/src/index.css
index 462ad161..9e60d4ca 100644
--- a/frontend/src/index.css
+++ b/frontend/src/index.css
@@ -244,6 +244,11 @@
       flex-direction: column;
     }
 
+    /* React Aria lists the newest toast first. */
+    [data-slot="toast-region"] li:not(:first-child) > [data-slot="toast"]:not(:focus-within) {
+      @apply sr-only;
+    }
+
     &::view-transition-new(.toast):only-child {
       animation-name: toast-slide-in-top;
     }
diff --git a/frontend/src/main.tsx b/frontend/src/main.tsx
index ddc36cc1..0735ec86 100644
--- a/frontend/src/main.tsx
+++ b/frontend/src/main.tsx
@@ -2,6 +2,7 @@ import { StrictMode } from 'react'
 import { createRoot } from 'react-dom/client'
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
 import { RouterProvider, createRouter } from '@tanstack/react-router'
+import { NotFound } from '@/components/not-found'
 import { ThemeProvider } from '@/components/theme-provider'
 import { Toaster } from '@/components/toaster'
 // Connects the generated API clients to apiClient before the first request.
@@ -12,7 +13,7 @@ import './index.css'
 import { routeTree } from './routeTree.gen'
 
 // Create a new router instance
-const router = createRouter({ routeTree })
+const router = createRouter({ routeTree, defaultNotFoundComponent: NotFound })
 
 // Register the router instance for type safety
 declare module '@tanstack/react-router' {
diff --git a/frontend/src/routes/__root.tsx b/frontend/src/routes/__root.tsx
index 90aa1a5a..9b16e30c 100644
--- a/frontend/src/routes/__root.tsx
+++ b/frontend/src/routes/__root.tsx
@@ -45,7 +45,8 @@ function RootComponent() {
   const router = useRouter()
   const routerState = useRouterState()
   const currentPath = routerState.location.pathname
-  const pageName = routeNames[currentPath] ?? 'Page'
+  const isNotFound = routerState.matches.some((match) => match.globalNotFound)
+  const pageName = isNotFound ? 'Not Found' : (routeNames[currentPath] ?? 'Page')
 
   return (
     <RouterProvider
diff --git a/frontend/src/routes/about.tsx b/frontend/src/routes/about.tsx
index f3362f4e..372a9b51 100644
--- a/frontend/src/routes/about.tsx
+++ b/frontend/src/routes/about.tsx
@@ -7,7 +7,7 @@ export const Route = createFileRoute('/about')({
 
 function About() {
   return (
-    <div className="min-h-screen bg-background">
+    <div className="bg-background">
       <main className="max-w-2xl mx-auto px-4 py-8">
         <Card>
           <CardHeader>
diff --git a/frontend/src/routes/components.tsx b/frontend/src/routes/components.tsx
index b1742f2a..1b0ed721 100644
--- a/frontend/src/routes/components.tsx
+++ b/frontend/src/routes/components.tsx
@@ -159,7 +159,7 @@ function ComponentsPage() {
 
   return (
     <>
-      <div className="w-full min-h-screen bg-linear-to-br from-bg-gradient-start to-bg-gradient-end text-text-primary">
+      <div className="w-full">
         <div className="max-w-[1200px] mx-auto px-8 py-10 max-md:px-4">
           {/* Header */}
           <div className="mb-10">
@@ -205,7 +205,7 @@ function ComponentsPage() {
                   <Button variant="link">Link</Button>
                 </div>
                 <Separator className="my-4" />
-                <div className="flex flex-wrap gap-4">
+                <div className="flex flex-wrap items-center gap-4">
                   <Button size="sm">Small</Button>
                   <Button size="default">Default</Button>
                   <Button size="lg">Large</Button>
diff --git a/frontend/src/routes/index.tsx b/frontend/src/routes/index.tsx
index f4f2df4b..665e4b20 100644
--- a/frontend/src/routes/index.tsx
+++ b/frontend/src/routes/index.tsx
@@ -64,7 +64,7 @@ function Index() {
   const handleLogout = () => auth.logoutUrl && logout(auth.logoutUrl)
 
   return (
-    <div className="min-h-screen bg-background">
+    <div className="bg-background">
       <main className="max-w-4xl mx-auto px-4 py-8">
         {/* Header */}
         <div className="flex items-center justify-between mb-8">
@@ -176,7 +176,7 @@ function Index() {
 
         {/* Loading State */}
         {isLoading && displayData.length === 0 && (
-          <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-4">
+          <div role="status" aria-label="Loading forecast" className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-4">
             {[...Array(6)].map((_, i) => (
               <Card key={i}>
                 <CardContent>
diff --git a/frontend/tests/features/app-shell/app-shell.locators.ts b/frontend/tests/features/app-shell/app-shell.locators.ts
new file mode 100644
index 00000000..f2e195d4
--- /dev/null
+++ b/frontend/tests/features/app-shell/app-shell.locators.ts
@@ -0,0 +1,9 @@
+import type { Page } from '@playwright/test'
+
+export const appShell = (page: Page) => ({
+  aboutText: page.getByText('This is a demo application built with .NET Aspire and React'),
+  currentPage: page.getByRole('navigation', { name: 'breadcrumb' }).getByRole('link'),
+  notFoundHeading: page.getByRole('heading', { name: 'Page not found' }),
+  homeLink: page.getByRole('link', { name: 'Go to the home page' }),
+  weatherHeading: page.getByRole('heading', { name: 'Weather Forecast' }),
+})
diff --git a/frontend/tests/features/app-shell/app-shell.spec.ts b/frontend/tests/features/app-shell/app-shell.spec.ts
new file mode 100644
index 00000000..6be41163
--- /dev/null
+++ b/frontend/tests/features/app-shell/app-shell.spec.ts
@@ -0,0 +1,57 @@
+import { weatherApi } from '@tests/support/api/weather-api'
+import { aForecast } from '@tests/support/builders/forecast-builder'
+import { expect, test } from '@tests/support/fixtures'
+import { weatherForecastPage } from '../weather/weather-forecast.tasks'
+import { appShellPage } from './app-shell.tasks'
+
+for (const viewport of [
+  { width: 1280, height: 800 },
+  { width: 390, height: 844 },
+]) {
+  test.describe(`a short page at ${viewport.width}x${viewport.height}`, () => {
+    test.use({ viewport })
+
+    test('does not scroll', async ({ page }) => {
+      const shell = appShellPage(page)
+
+      await shell.openAbout()
+
+      expect(await shell.pageScrollRange()).toBe(0)
+    })
+  })
+}
+
+test.describe('the home page on a desktop', () => {
+  test.use({ viewport: { width: 1280, height: 800 } })
+
+  test('does not scroll when the forecast fits', async ({ page, api }) => {
+    api.mock(weatherApi.listReturns(aForecast().on('2026-03-14'), aForecast().on('2026-03-15'), aForecast().on('2026-03-16')))
+
+    await weatherForecastPage(page).open()
+
+    expect(await appShellPage(page).pageScrollRange()).toBe(0)
+  })
+})
+
+test.describe('an unknown address', () => {
+  test('shows a page not found message in the app layout', async ({ page }) => {
+    const shell = appShellPage(page)
+
+    await shell.openMissingPage()
+
+    await expect(shell.at.notFoundHeading).toBeVisible()
+    await expect(shell.at.currentPage).toHaveText('Not Found')
+    expect(shell.warnings.filter((warning) => warning.includes('notFound'))).toEqual([])
+  })
+
+  test('links to the home page', async ({ page, api }) => {
+    api.mock(weatherApi.listReturns(aForecast()))
+    const shell = appShellPage(page)
+    await shell.openMissingPage()
+
+    await shell.goHome()
+
+    await expect(shell.at.weatherHeading).toBeVisible()
+    await expect(shell.at.currentPage).toHaveText('Home')
+  })
+})
diff --git a/frontend/tests/features/app-shell/app-shell.tasks.ts b/frontend/tests/features/app-shell/app-shell.tasks.ts
new file mode 100644
index 00000000..ea6572d0
--- /dev/null
+++ b/frontend/tests/features/app-shell/app-shell.tasks.ts
@@ -0,0 +1,38 @@
+import { expect, type Page } from '@playwright/test'
+import { weatherPaths } from '@tests/support/api/weather-api'
+import { appShell } from './app-shell.locators'
+
+export function appShellPage(page: Page) {
+  const at = appShell(page)
+  const warnings: string[] = []
+  page.on('console', (message) => {
+    if (message.type() === 'warning') warnings.push(message.text())
+  })
+
+  return {
+    at,
+    warnings,
+
+    async openAbout() {
+      await page.goto('/about')
+      await expect(at.aboutText).toBeVisible()
+    },
+
+    async openMissingPage() {
+      await page.goto('/no-such-page')
+      await expect(at.currentPage).toBeVisible()
+    },
+
+    async goHome() {
+      const settled = page.waitForResponse(
+        (r) => r.request().method() === 'GET' && new URL(r.url()).pathname === weatherPaths.list,
+      )
+      await at.homeLink.click()
+      await settled
+    },
+
+    async pageScrollRange() {
+      return page.evaluate(() => document.documentElement.scrollHeight - document.documentElement.clientHeight)
+    },
+  }
+}
diff --git a/frontend/tests/features/filter-demo/filter-demo.locators.ts b/frontend/tests/features/filter-demo/filter-demo.locators.ts
index 8b6d04f5..9254bf18 100644
--- a/frontend/tests/features/filter-demo/filter-demo.locators.ts
+++ b/frontend/tests/features/filter-demo/filter-demo.locators.ts
@@ -10,6 +10,8 @@ export const filterDemo = (page: Page) => {
     property: (propertyLabel: string) => page.getByRole('menuitem', { name: propertyLabel, exact: true }),
     control,
     loadingControl: page.getByRole('status', { name: 'Loading filter' }),
+    valueGroup: (propertyLabel: string) => control(propertyLabel).getByRole('group', { name: propertyLabel, exact: true }),
+    controlLabel: (propertyLabel: string) => control(propertyLabel).getByText(propertyLabel, { exact: true }),
     quickSelect: (propertyLabel: string, name: string) => control(propertyLabel).getByRole('button', { name, exact: true }),
     addFilter: (propertyLabel: string) => control(propertyLabel).getByRole('button', { name: 'Add Filter', exact: true }),
     removeFilter: (propertyLabel: string) => page.getByRole('button', { name: new RegExp(`^Remove filter: ${propertyLabel}`) }),
diff --git a/frontend/tests/features/filter-demo/filter-demo.spec.ts b/frontend/tests/features/filter-demo/filter-demo.spec.ts
index 434654cd..5e17d185 100644
--- a/frontend/tests/features/filter-demo/filter-demo.spec.ts
+++ b/frontend/tests/features/filter-demo/filter-demo.spec.ts
@@ -1,4 +1,5 @@
 import { test, expect } from '@tests/support/fixtures'
+import { takesUpSpace } from '@tests/support/screen'
 import { filterDemoPage } from './filter-demo.tasks'
 
 const phone = { width: 390, height: 844 }
@@ -19,6 +20,16 @@ test.describe('the Add Filter menu on a phone', () => {
     })
   }
 
+  test('names the Is Blocked control only in the title of the sheet', async ({ page }) => {
+    const demo = filterDemoPage(page)
+    await demo.open()
+
+    await demo.chooseProperty('Is Blocked')
+
+    expect(await takesUpSpace(demo.at.controlLabel('Is Blocked'))).toBe(false)
+    await expect(demo.at.valueGroup('Is Blocked')).toBeVisible()
+  })
+
   test('adds a date filter from its control', async ({ page }) => {
     const demo = filterDemoPage(page)
     await demo.open()
@@ -54,6 +65,16 @@ for (const screen of [
 test.describe('the Add Filter menu on a desktop', () => {
   test.use({ viewport: { width: 1280, height: 800 } })
 
+  test('names the Is Blocked control in the menu', async ({ page }) => {
+    const demo = filterDemoPage(page)
+    await demo.open()
+
+    await demo.chooseProperty('Is Blocked')
+
+    expect(await takesUpSpace(demo.at.controlLabel('Is Blocked'))).toBe(true)
+    await expect(demo.at.valueGroup('Is Blocked')).toBeVisible()
+  })
+
   test('shows the Created Date control beside the open menu', async ({ page }) => {
     const demo = filterDemoPage(page)
     await demo.open()
diff --git a/frontend/tests/features/toasts/toasts.locators.ts b/frontend/tests/features/toasts/toasts.locators.ts
new file mode 100644
index 00000000..32c880d3
--- /dev/null
+++ b/frontend/tests/features/toasts/toasts.locators.ts
@@ -0,0 +1,13 @@
+import type { Page } from '@playwright/test'
+
+export type ToastButton = 'Success' | 'Error' | 'Info' | 'Warning'
+
+export const toastDemo = (page: Page) => ({
+  heading: page.getByRole('heading', { name: 'Component Library' }),
+  showToast: (name: ToastButton) => page.getByRole('button', { name, exact: true }),
+  openDialog: page.getByRole('button', { name: 'Open Dialog', exact: true }),
+  dialog: page.getByRole('dialog', { name: 'Dialog Title' }),
+  region: page.getByRole('region', { name: /notification/ }),
+  toasts: page.getByRole('alertdialog'),
+  toast: (message: string) => page.getByRole('alertdialog').filter({ hasText: message }),
+})
diff --git a/frontend/tests/features/toasts/toasts.spec.ts b/frontend/tests/features/toasts/toasts.spec.ts
new file mode 100644
index 00000000..288ec0a2
--- /dev/null
+++ b/frontend/tests/features/toasts/toasts.spec.ts
@@ -0,0 +1,43 @@
+import { expect, test } from '@tests/support/fixtures'
+import { toastDemoPage } from './toasts.tasks'
+
+test.describe('the toast region', () => {
+  test('shows a focus ring when F6 moves the focus to it', async ({ page }) => {
+    const demo = toastDemoPage(page)
+    await demo.open()
+    await demo.showToastsByKeyboard('Success')
+
+    await demo.moveFocusToToasts()
+
+    expect(await demo.hasFocusRing(demo.at.region)).toBe(true)
+  })
+})
+
+// React Aria lists the newest toast first.
+test.describe('the toasts on a phone on its side while a bottom sheet is open', () => {
+  test.use({ viewport: { width: 667, height: 375 } })
+
+  test('show only the newest toast, and keep the others for a screen reader', async ({ page }) => {
+    const demo = toastDemoPage(page)
+    await demo.open()
+    await demo.showToastsByKeyboard('Success', 'Error', 'Info')
+
+    await demo.openBottomSheet()
+
+    expect(await demo.shownToasts()).toEqual(['A new version is available'])
+    expect(await demo.at.toasts.count()).toBe(3)
+  })
+
+  test('show an older toast while it has the keyboard focus', async ({ page }) => {
+    const demo = toastDemoPage(page)
+    await demo.open()
+    await demo.showToastsByKeyboard('Success', 'Error', 'Info')
+    await demo.openBottomSheet()
+
+    await demo.moveFocusToToasts()
+    await demo.pressTab(3)
+
+    await expect(demo.at.toast('Something went wrong')).toBeFocused()
+    expect(await demo.shownToasts()).toEqual(['A new version is available', 'Something went wrong'])
+  })
+})
diff --git a/frontend/tests/features/toasts/toasts.tasks.ts b/frontend/tests/features/toasts/toasts.tasks.ts
new file mode 100644
index 00000000..35033d1b
--- /dev/null
+++ b/frontend/tests/features/toasts/toasts.tasks.ts
@@ -0,0 +1,52 @@
+import { expect, type Locator, type Page } from '@playwright/test'
+import { takesUpSpace } from '@tests/support/screen'
+import { toastDemo, type ToastButton } from './toasts.locators'
+
+export function toastDemoPage(page: Page) {
+  const at = toastDemo(page)
+
+  return {
+    at,
+
+    async open() {
+      await page.goto('/components')
+      await expect(at.heading).toBeVisible()
+    },
+
+    async showToastsByKeyboard(...buttons: ToastButton[]) {
+      for (const button of buttons) await at.showToast(button).press('Enter')
+      await expect(at.toasts).toHaveCount(buttons.length)
+    },
+
+    async openBottomSheet() {
+      await at.openDialog.press('Enter')
+      await expect(at.dialog).toBeVisible()
+    },
+
+    async moveFocusToToasts() {
+      await page.keyboard.press('F6')
+      await expect(at.region).toBeFocused()
+    },
+
+    async pressTab(times: number) {
+      for (let i = 0; i < times; i++) await page.keyboard.press('Tab')
+    },
+
+    async shownToasts() {
+      const shown: string[] = []
+      for (const toast of await at.toasts.all()) {
+        if (await takesUpSpace(toast)) shown.push((await toast.innerText()).split('\n')[0])
+      }
+      return shown
+    },
+
+    async hasFocusRing(element: Locator) {
+      return element.evaluate((node) => {
+        const { outlineStyle, outlineWidth, boxShadow } = getComputedStyle(node)
+        if (outlineStyle !== 'none' && parseFloat(outlineWidth) > 0) return true
+        const spreads = [...boxShadow.matchAll(/-?[\d.]+px -?[\d.]+px [\d.]+px (?<spread>-?[\d.]+)px/g)].map((m) => Number(m.groups?.spread))
+        return spreads.some((spread) => spread >= 1)
+      })
+    },
+  }
+}
diff --git a/frontend/tests/features/weather/weather-forecast.locators.ts b/frontend/tests/features/weather/weather-forecast.locators.ts
index 12547ef3..0266971e 100644
--- a/frontend/tests/features/weather/weather-forecast.locators.ts
+++ b/frontend/tests/features/weather/weather-forecast.locators.ts
@@ -13,6 +13,7 @@ export const weatherForecast = (page: Page) => {
     celsius: page.getByRole('button', { name: '°C', exact: true }),
     refresh: page.getByRole('button', { name: 'Refresh', exact: true }),
     tryAgain: page.getByRole('button', { name: 'Try Again', exact: true }),
+    loading: page.getByRole('status', { name: 'Loading forecast' }),
     emptyMessage: page.getByText('No weather data available'),
     error: page.getByRole('alert').filter({ hasText: 'Error loading weather data' }),
     toast: (text: string) => page.getByRole('alertdialog').filter({ hasText: text }),
diff --git a/frontend/tests/features/weather/weather-forecast.spec.ts b/frontend/tests/features/weather/weather-forecast.spec.ts
index b5527c16..3a60c0aa 100644
--- a/frontend/tests/features/weather/weather-forecast.spec.ts
+++ b/frontend/tests/features/weather/weather-forecast.spec.ts
@@ -140,3 +140,29 @@ test.describe('a signed-in user', () => {
     expect(api.last('get', bffPaths.logout)?.query.get('sid')).toBe('test-session')
   })
 })
+
+test.describe('the loading placeholders', () => {
+  const slowList = { ...weatherApi.listReturns(aForecast()), delayMs: 2_000 }
+
+  test('hold still for a user who asks for reduced motion', async ({ page, api }) => {
+    api.mock(slowList)
+    const weather = weatherForecastPage(page)
+
+    await weather.openWhileLoading()
+
+    expect(await weather.runningAnimationsIn(weather.at.loading)).toBe(0)
+  })
+
+  test.describe('without a reduced motion preference', () => {
+    test.use({ reducedMotion: 'no-preference' })
+
+    test('pulse', async ({ page, api }) => {
+      api.mock(slowList)
+      const weather = weatherForecastPage(page)
+
+      await weather.openWhileLoading()
+
+      expect(await weather.runningAnimationsIn(weather.at.loading)).toBeGreaterThan(0)
+    })
+  })
+})
diff --git a/frontend/tests/features/weather/weather-forecast.tasks.ts b/frontend/tests/features/weather/weather-forecast.tasks.ts
index d888b5e7..26278395 100644
--- a/frontend/tests/features/weather/weather-forecast.tasks.ts
+++ b/frontend/tests/features/weather/weather-forecast.tasks.ts
@@ -1,4 +1,4 @@
-import { expect, type Page } from '@playwright/test'
+import { expect, type Locator, type Page } from '@playwright/test'
 import { bffPaths } from '@tests/support/api/bff-api'
 import { weatherPaths } from '@tests/support/api/weather-api'
 import { weatherForecast } from './weather-forecast.locators'
@@ -19,6 +19,15 @@ export function weatherForecastPage(page: Page) {
       await settled
     },
 
+    async openWhileLoading() {
+      await page.goto('/')
+      await expect(at.loading).toBeVisible()
+    },
+
+    async runningAnimationsIn(element: Locator) {
+      return element.evaluate((node) => node.getAnimations({ subtree: true }).length)
+    },
+
     async showInCelsius() {
       await at.celsius.click()
     },
diff --git a/frontend/tests/support/screen.ts b/frontend/tests/support/screen.ts
new file mode 100644
index 00000000..12cd0521
--- /dev/null
+++ b/frontend/tests/support/screen.ts
@@ -0,0 +1,9 @@
+import type { Locator } from '@playwright/test'
+
+// A visually hidden element (Tailwind sr-only) is 1 px by 1 px, and Playwright counts it as visible.
+const visuallyHiddenSizePx = 1
+
+export async function takesUpSpace(element: Locator): Promise<boolean> {
+  const box = await element.boundingBox()
+  return box !== null && box.width > visuallyHiddenSizePx && box.height > visuallyHiddenSizePx
+}