Handling different client and server content - not showing initial render

In the hydrateRoot page, it is mentioned that
"This way the initial render pass will render the same content as the server, avoiding mismatches, but an additional pass will happen synchronously right after hydration."

which means that the initial render on the playground should show "Is Server", but it shows directly "Is Client" which is very confusing for learners and doesn't show the real behavior.
I tired opening the sandbox in external window, and it indeed shows "Is Server" first and then changing to "Is Client" as expected.

Comienza con el playground integrado en la página de hydrateRoot y compara su comportamiento con el de la misma sandbox abierta externamente. Verifica que el renderizado inicial muestre "Is Server" antes de cambiar a "Is Client"; se considera terminado cuando el ejemplo integrado demuestra la secuencia de hidratación documentada.