[Bug]: Mobile webkit tests on Ubuntu works 4x slower in comparison with macOS

[Ihor123166]

Version

1.49.1

Steps to reproduce

1. git clone https://github.com/Ihor123166/mobile-safari-bug-on-ubuntu.git
2. cd mobile-safari-bug-on-ubuntu
3. Install yarn if needed npm install -g yarn
4. Install dependencies yarn && yarn playwright install --with-deps
5. Install docker if needed
6. Run tests on ubuntu docker run -it --rm --ipc=host -v ./:/tests mcr.microsoft.com/playwright:v1.49.1 /bin/bash -c "cd /tests && yarn playwright test tests/slow.spec.ts"

Expected behavior

Expect mobile WebKit tests on Ubuntu to pass at approximately the same speed as on macOS

Actual behavior

Mobile webkit tests on Ubuntu passed 4-5x slower in comparison with macOS. But other projects doesn't have such big difference in speed

Additional context

No response

Environment

System:
    OS: macOS 15.2
    CPU: (10) arm64 Apple M1 Pro
    Memory: 100.48 MB / 16.00 GB
  Binaries:
    Node: 22.11.0 - ~/.nvm/versions/node/v22.11.0/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
  Languages:
    Bash: 3.2.57 - /bin/bash
  npmPackages:
    @playwright/test: ^1.49.1 => 1.49.1

[pavelfeldman]

I can repro, unclear what is going on, looks like dedicated WebKit headless implementation on Linux (WPE) is hammered with rendering.

As a workaround, you can run your tests in a headed mode under xvfb:

    {
      name: "Mobile Safari",
      use: {
        ...devices["iPhone 12"],
        headless: false,
      },
    },

[pavelfeldman]

Also, ToT seems to be working fine:

npm i @playwright/test@1.50.0-alpha-2024-12-20

[Ihor123166]

@pavelfeldman Thank you, the workaround helped me, and it's working fine on version 1.50.0-alpha-2024-12-20 for me too