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Playwright Multi-Tab & Window Handling

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Teaches the agent to handle popups, new tabs, and multiple browser windows in Playwright using waitForEvent('page'), context pages, and reliable tab switching for OAuth and target=_blank links.

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Playwright Multi-Tab & Window Handling

This skill makes the agent write correct, race-free code for any flow that opens a second tab or popup: target="_blank" links, "Open in new window" buttons, OAuth/SSO consent screens, payment redirects, and PDF preview tabs. The central rule is that a new page is an event you must subscribe to before the click, never a thing you poll for afterward.

Use this skill whenever a test clicks something and a new tab/window appears, or whenever the agent sees page.waitForTimeout being used to "wait for the popup."

Core Principles

  1. Subscribe before you click. Register context.waitForEvent('page') (or page.waitForEvent('popup')) before the action that triggers the popup, then await both together. Subscribing after the click is a race.
  2. A tab belongs to a BrowserContext, not a Page. All tabs in one context share cookies/storage. context.pages() is the live list of open tabs.
  3. Always await newPage.waitForLoadState() before asserting — the page object resolves the moment the tab exists, not when it has loaded.
  4. Switch by holding a reference, never by index. Index order is not guaranteed across browsers. Capture the returned Page object.
  5. Close popups you opened. Leaked tabs slow the suite and can hold modal focus. Close them or rely on context teardown.
  6. Cross-origin popups are fine within a context. OAuth on a different domain still arrives as a page event; you do not need a new context.

Workflow / Patterns

Pattern 1 — Capture a popup from a target="_blank" link

The canonical, race-free shape uses Promise.all: start listening, then click, in one expression.

import { test, expect } from '@playwright/test';

test('opens docs in a new tab', async ({ context, page }) => {
  await page.goto('https://example.com/app');

  // Subscribe BEFORE the click, await both together.
  const [newPage] = await Promise.all([
    context.waitForEvent('page'),
    page.getByRole('link', { name: 'Open docs' }).click(),
  ]);

  // The page object exists, but the tab may still be loading.
  await newPage.waitForLoadState('domcontentloaded');

  await expect(newPage).toHaveURL(/\/docs/);
  await expect(newPage.getByRole('heading', { name: 'Documentation' })).toBeVisible();

  await newPage.close();
  // Original tab is still fully usable.
  await expect(page.getByRole('button', { name: 'Back to app' })).toBeVisible();
});

Pattern 2 — page.waitForEvent('popup') for window.open

When the element calls window.open(), the popup event on the opener page is the most precise listener — it ties the new page to the exact opener.

test('handles a window.open popup', async ({ page }) => {
  await page.goto('https://example.com/share');

  const popupPromise = page.waitForEvent('popup');
  await page.getByRole('button', { name: 'Share to LinkedIn' }).click();
  const popup = await popupPromise;

  await popup.waitForLoadState();
  await expect(popup).toHaveURL(/linkedin\.com/);
  await popup.close();
});

Pattern 3 — Multi-tab OAuth / SSO consent flow

The provider page opens in a popup, you authenticate there, the popup closes itself, and the original tab becomes authenticated. Wait for the popup to close before asserting on the main page.

test('logs in via Google OAuth popup', async ({ page }) => {
  await page.goto('https://example.com/login');

  const popupPromise = page.waitForEvent('popup');
  await page.getByRole('button', { name: 'Continue with Google' }).click();
  const oauth = await popupPromise;

  // Drive the provider's consent screen inside the popup.
  await oauth.waitForLoadState('domcontentloaded');
  await oauth.getByLabel('Email').fill(process.env.OAUTH_EMAIL!);
  await oauth.getByRole('button', { name: 'Next' }).click();
  await oauth.getByLabel('Password').fill(process.env.OAUTH_PASSWORD!);
  await oauth.getByRole('button', { name: 'Sign in' }).click();
  await oauth.getByRole('button', { name: 'Allow' }).click();

  // The provider closes its own window; wait for that, then assert on main page.
  await oauth.waitForEvent('close');
  await expect(page.getByText('Signed in as')).toBeVisible({ timeout: 15_000 });
});

Pattern 4 — Several tabs open at once, switch deterministically

Hold each Page in a variable. Never rely on context.pages()[1] order.

test('manages three tabs by reference', async ({ context, page }) => {
  await page.goto('https://example.com/reports');

  const [reportA] = await Promise.all([
    context.waitForEvent('page'),
    page.getByRole('link', { name: 'Report A' }).click(),
  ]);
  const [reportB] = await Promise.all([
    context.waitForEvent('page'),
    page.getByRole('link', { name: 'Report B' }).click(),
  ]);

  await reportA.waitForLoadState();
  await reportB.waitForLoadState();

  // Bring a specific tab to the foreground (affects screenshots / focus).
  await reportB.bringToFront();
  await expect(reportB.getByRole('heading')).toHaveText('Report B');

  await reportA.bringToFront();
  await expect(reportA.getByRole('heading')).toHaveText('Report A');

  // context.pages() === [page, reportA, reportB] — but assert by reference, not index.
  expect(context.pages()).toHaveLength(3);
});

Pattern 5 — Reusable helper to capture and load a new tab

Wrap the race-free dance once so tests stay readable.

import { type BrowserContext, type Page } from '@playwright/test';

/** Runs `action`, returns the newly opened, fully-loaded tab. */
export async function openInNewTab(
  context: BrowserContext,
  action: () => Promise<void>,
  loadState: 'load' | 'domcontentloaded' | 'networkidle' = 'domcontentloaded',
): Promise<Page> {
  const [newPage] = await Promise.all([context.waitForEvent('page'), action()]);
  await newPage.waitForLoadState(loadState);
  return newPage;
}

// Usage:
test('uses the helper', async ({ context, page }) => {
  await page.goto('https://example.com');
  const invoice = await openInNewTab(context, () =>
    page.getByRole('link', { name: 'View invoice' }).click(),
  );
  await expect(invoice).toHaveTitle(/Invoice/);
  await invoice.close();
});

Pattern 6 — Force same-tab navigation when you do NOT want a popup

Sometimes a target="_blank" link makes assertions harder than they need to be. Strip the attribute before clicking so navigation stays in one page.

test('forces same-tab navigation', async ({ page }) => {
  await page.goto('https://example.com');
  const link = page.getByRole('link', { name: 'Terms' });
  await link.evaluate((el) => el.removeAttribute('target'));
  await link.click();
  await expect(page).toHaveURL(/\/terms/);
});

Best Practices

  1. Use Promise.all([waitForEvent, click]) as the default shape — it makes the subscribe-before-click ordering structurally impossible to get wrong.
  2. Prefer page.waitForEvent('popup') over context.waitForEvent('page') when one specific element triggers the new window — it scopes the wait to the right opener.
  3. Always waitForLoadState on the new page before any locator or URL assertion.
  4. Type your helpers (Page, BrowserContext) so downstream tests get autocomplete and the popup is never any.
  5. For OAuth, wait on popup.waitForEvent('close') as the signal that auth finished, then assert on the main page.
  6. Set a generous timeout on the post-popup assertion (OAuth redirects are slow); 15s is reasonable.
  7. Reuse storageState for repeated logins instead of driving the OAuth popup in every test — drive it once in global setup, save state, reuse it.

Anti-Patterns

  1. Clicking, then calling context.waitForEvent('page'). The event may already have fired; you will hang until timeout. Subscribe first.
  2. await page.waitForTimeout(3000) to "let the tab open." Flaky and slow. Use the event.
  3. Selecting the tab via context.pages()[1]. Tab order is not portable across Chromium/Firefox/WebKit. Hold the returned reference.
  4. Asserting on a new page before waitForLoadState. The page object exists immediately; its content does not.
  5. Spawning a fresh browser.newContext() for an OAuth popup. A popup in the same context shares the session you need; a new context throws away cookies.
  6. Leaving popups open across many tests — memory grows and focus-stealing modals cause unrelated failures.
  7. Driving the main page while the popup is mid-auth. Finish the popup flow (or wait for its close) first.

When to Trigger This Skill

  • "Clicking this link opens a new tab and my test can't find the element"
  • "How do I handle a popup / window.open in Playwright?"
  • "Test the Google / GitHub / SSO OAuth login flow"
  • "A target=_blank link breaks my assertions"
  • "I have multiple tabs open and need to switch between them"
  • "Handle the payment redirect that opens in a new window"
  • "My popup test is flaky / times out waiting for the new page"