Whenever trying to join someone's realms I can destroy blocks for about 3 seconds and then I get kicked with this message: "java.io.IOException: An existing connection was forcibly closed by the remote host". Reinstalling Minecraft, changing wifi connection, disabling firewall and antivirus, etc. doesn't fix this issue so I can assume a problem is within the code itself. Especially because on version 1.13.2 a while ago there was no problem.
EDIT:
I found temporary fix for this issue:
Turn off PVP
Turn on PVP again
Server gonna restart and you should be able to join and play for some time, when it kicks you again just repeat step 1, 2.
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Thank you for your report!
This is a technical support issue, which we're already tracking in MC-38565, so I resolved and linked this ticket as a duplicate. We do not have the resources to provide you with technical support.
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Same happens to me, Mojang if u read this pls email me about how to fix. I cant play realms :_: