In every server, every version, but not in the singleplayer I have the same bug. What bug does, is it leaves server when I go to out of Minecraft and open any file or program and wait 15 seconds, and comes error which says "Internal Exception: java.io.IOException: An existing connection was forcibly closed by the remote host" I tried everything to fix it, even I deleted Minecraft and downloaded again and reset all settings, but it is not fixing. I think it can be due to my internet maybe? Thank you for even trying to help <3!