Playwright: Execution context was destroyed, most likely because of a navigation

Every document has a JavaScript execution context. When the page navigates, reloads or a frame changes documents, the old context is thrown away. Any page.evaluate(), locator.evaluate() or handle-based call that was running in, or bound to, the old context fails with this message, because the code it was running and the objects it referenced no longer exist.

It usually shows up when an action triggers a navigation (a form submit, a redirect after login, a client-side reload) and the next line evaluates script before the new document is ready, or when a site performs a redirect chain on its own. With locators and auto-waiting actions it is rare, because those are retried in the new context automatically.

What is not wrong: your script logic. It ran against a page that disappeared halfway through.

// JavaScript
await page.getByRole('button', { name: 'Log in' }).click();
await page.waitForURL('**/dashboard');
const user = await page.evaluate(() => window.__USER__);

# Python
page.get_by_role("button", name="Log in").click()
page.wait_for_url("**/dashboard")
user = page.evaluate("() => window.__USER__")

Pair every navigating action with an explicit wait for the destination URL or element. Keep evaluate calls short and stateless so they can be safely re-run, and avoid passing handles across navigations. Most such flows can be written entirely with locators, which removes the problem.