I'm playing this map; https://www.planetminecraft.com/project/skyblock-1-18-5459050/
No mods, datapack should not interfere with game mechanics.
Went to -63 and made a one block falling water at (y=64) glowsquid spawner to collect loot. Sometimes, when the drops just barely touch the water stream, they float upwards.
Thank you for your report!
However, this issue is Invalid.
Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.
Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.
Any plugin issues need to be addressed to the creator of the plugin or resource pack.
If you have problems on large servers, such as The Hive and Hypixel, please contact them first as they run modified server software.
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