[Bug]: setViewportSize leads to timeouts running tests in firefox

[pascalknupper]

Version

1.53.0

Steps to reproduce

1. clone my repo https://github.com/pascalknupper/pw-firefox-setViewport
2. install deps
3. run npx playwright test -> leads to timeouts in firefox project
4. run npx playwright test --ui -> leads to no timeouts in firefox project

Expected behavior

Viewport should be updated during test execution. see example

Actual behavior

Running tests in Firefox project and setting viewport during tests seems to cause some issues. In latest version we are running into timeout exceptions.

Additional context

No response

Environment

System:
    OS: macOS 15.5
    CPU: (10) arm64 Apple M1 Pro
    Memory: 205.64 MB / 32.00 GB
  Binaries:
    Node: 20.11.0 - ~/.asdf/installs/nodejs/20.11.0/bin/node
    npm: 10.2.4 - ~/.asdf/installs/nodejs/20.11.0/bin/npm
  IDEs:
    VSCode: 1.100.3 - /opt/homebrew/bin/code
  Languages:
    Bash: 5.2.37 - /opt/homebrew/bin/bash
  npmPackages:
    @playwright/test: ^1.53.0 => 1.53.0

[dgozman]

I can repro, thank you for the issue.

[dgozman]

This should be fixed by #36340. Unfortunately, I was not able to write a reliable test for this timing issue.