Fixed inventory slots being reused incorrectly in rare cases in the JEI transfer handler. Fixes #3431

CHANGELOG.md

@@ -11,6 +11,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 - Fixed external storage cache being de-synced from the network cache.
 - Fixed external storage using an out of date block entity for getting handler.
+- Fixed inventory slots being reused incorrectly in rare cases in the JEI transfer handler.
 
 ### Changed
 

src/main/java/com/refinedmods/refinedstorage/integration/jei/IngredientTracker.java

@@ -205,7 +205,7 @@ public class IngredientTracker {
             int amount = Math.min(ingredient.getMissingAmount(), used == null ? stackInSlot.getCount() : stackInSlot.getCount() - used);
             if (amount > 0) {
                 ingredient.fulfill(amount);
-                usedMatrixStacks.put(slot, amount);
+                usedMatrixStacks.put(slot, used == null ? amount : used + amount);
             }
             return ingredient.isAvailable();
         }