[Bug]: slowMo prevents waitForResponse

[das-en]

Version

1.50.0

Steps to reproduce

Use the slowMo launch option, for example in my config:
launchOptions: { slowMo: 250 }
and have a test/method that uses waitForResponse

Expected behavior

Ideally the default behavior/results would still work even with slowMo applied. If not, perhaps a documentation update would be helpful.

Actual behavior

instances of using waitForResponse will result in immediate failure as the slowMo appears to prevent normal behavior. The waitForResponse timeout duration does not seem to matter as mine is set to 25000.

Additional context

No response

Environment

System:
    OS: macOS 15.4.1
    CPU: (16) arm64 Apple M4 Max
    Memory: 1.63 GB / 48.00 GB
  Binaries:
    Node: 22.15.0 - /usr/local/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
    npm: 10.9.2 - /usr/local/bin/npm
    pnpm: 9.12.3 - /opt/homebrew/bin/pnpm
  Languages:
    Bash: 3.2.57 - /bin/bash
  npmPackages:
    @playwright/test: 1.50.0 => 1.50.0

[yury-s]

Please share a reproduction that we could run locally. Worked fine for me with the following test:

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

test.use({
  launchOptions: {
    slowMo: 1000,
  },
});

test('slowMo should not break waitForResponse', async ({ page }) => {
  const promise = page.waitForResponse(response => response.url().includes('https://playwright.dev') && response.status() === 200);
  await page.goto('https://playwright.dev');
  const response = await promise;
  expect(response.status()).toBe(200);
});

[yury-s]

We need a minimal reproduction that we could run locally to make this report actionable. Please file a new one and link to this issue when you get back to it!