diff --git a/nms-patches/ExpiringMap.patch b/nms-patches/ExpiringMap.patch
new file mode 100644
index 0000000000..874be6879a
--- /dev/null
+++ b/nms-patches/ExpiringMap.patch
@@ -0,0 +1,61 @@
+--- a/net/minecraft/server/ExpiringMap.java
++++ b/net/minecraft/server/ExpiringMap.java
+@@ -4,8 +4,10 @@
+ import it.unimi.dsi.fastutil.longs.Long2LongMap;
+ import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+ import it.unimi.dsi.fastutil.longs.Long2LongMap.Entry;
++import it.unimi.dsi.fastutil.objects.ObjectCollection;
+ import it.unimi.dsi.fastutil.objects.ObjectIterator;
+ import java.util.Map;
++import java.util.function.LongFunction;
+ 
+ public class ExpiringMap<T> extends Long2ObjectOpenHashMap<T> {
+ 
+@@ -21,11 +23,17 @@
+         long j = SystemUtils.b();
+ 
+         this.b.put(i, j);
+-        ObjectIterator objectiterator = this.b.long2LongEntrySet().iterator();
++        cleanup();
++        // CraftBukkit start
++    }
++
++    public void cleanup() {
++        long j = SystemUtils.b();
++        ObjectIterator<Long2LongMap.Entry> objectiterator = this.b.long2LongEntrySet().iterator(); // CraftBukkit - decompile error
+ 
+         while (objectiterator.hasNext()) {
+-            Entry entry = (Entry) objectiterator.next();
+-            Object object = super.get(entry.getLongKey());
++            Long2LongMap.Entry entry = (Long2LongMap.Entry) objectiterator.next(); // CraftBukkit - decompile error
++            T object = super.get(entry.getLongKey()); // CraftBukkit - decompile error
+ 
+             if (j - entry.getLongValue() <= (long) this.a) {
+                 break;
+@@ -36,6 +44,7 @@
+                 objectiterator.remove();
+             }
+         }
++        // CraftBukkit end
+ 
+     }
+ 
+@@ -69,4 +78,18 @@
+     public T remove(Object object) {
+         throw new RuntimeException("Not implemented");
+     }
++
++    // CraftBukkit start
++    @Override
++    public T computeIfAbsent(long l, LongFunction<? extends T> lf) {
++        this.b.put(l, SystemUtils.b());
++        return super.computeIfAbsent(l, lf);
++    }
++
++    @Override
++    public ObjectCollection<T> values() {
++        cleanup();
++        return super.values();
++    }
++    // CraftBukkit end    
+ }