friend can't see NPCs or other players on every single Java server.

Thank you for your report!
However, this issue is Invalid.

This is a technical support issue, this website is to track bugs for the game and we do not have the tools to assist with technical issues here.
Please check the Technical Support Resources, or the Community Support Discord - please note that technical support for Minecraft is done by volunteers, so please be patient if you do not receive an answer right away.

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