Minecraft 1.21.1 · NeoForge 21.1.251+ · Java 21 · Client and Server

Blood Bits: Flow 2.9.1.1

A small but important stacking fix on top of 2.9.1.

Fixed: dirty and wet items not stacking

• Items with dirt, mud, soot, snow, frost or wetness can now stack with matching dirty items and with clean items of the same kind, just as blood-stained items already could.
• Previously, any difference in grime amount, wetness or deposit time could prevent merging in inventories, containers, hoppers, standard item handlers and dropped-item piles.
• Grime is now excluded from the stacking comparison and mixed when stacks merge. Each layer is averaged by item count: one dirty item combined with three clean items leaves one quarter of the original grime level.
• Other item differences, including enchantments, names and unrelated mod data, still prevent incompatible stacks from merging.

Compatibility

• Save format, network protocol, mod ID and public API are unchanged from 2.9.1.
• Update both clients and the server to 2.9.1.1 to apply the fix consistently.
• The 2.9.x save-format limitation still applies: opening these worlds in 2.8.3 or older loses blood stored in the newer format. Keep a backup before downgrading.

Known limitation

Modded storage systems that use their own item-comparison code instead of standard Forge/NeoForge item handlers may still keep clean and dirty stacks separate.