How to don't show page

"not showing the web page", if you mean headless mode by that, you can configure that by setting use: { headless: true } in the config. Note that headless mode is the default, so you should check for overrides.

Thank you !

I have a test that works with headless: false and doesn't work when the headless is set to true.

is it normal ?

To solve this we need to set headless to true right?

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║ Looks like you launched a headed browser without having a XServer running.                     ║
║ Set either 'headless: true' or use 'xvfb-run <your-playwright-app>' before running Playwright. ║
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║ <3 Playwright Team                                                                             ║
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Yes