In version 18w47a, there're problems loading maps from the old versions. The logic's thread is completely locked-up (mob's AI not working, no items dropped when the block is destroyed). When a player is outside the boundary of the loaded chunck, the player will fall down from the edge very slowly (like falling from the cliff, but much slower). If loading a map generated by the new version, even though it does not locked-up, but it loads much slower than previous version. Don't let me wait for the map because it's still locked-up!!!
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Please attach the crash report (
[minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt
), otherwise we can not diagnose this issue.For technical support please use the Mojang Support Center.
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