diff --git a/src/main/java/com/cleanroommc/modularui/value/sync/PanelSyncManager.java b/src/main/java/com/cleanroommc/modularui/value/sync/PanelSyncManager.java
index c05ac874d..a5933373f 100644
--- a/src/main/java/com/cleanroommc/modularui/value/sync/PanelSyncManager.java
+++ b/src/main/java/com/cleanroommc/modularui/value/sync/PanelSyncManager.java
@@ -60,7 +60,13 @@ public PanelSyncManager(ModularSyncManager msm, boolean main) {
     @ApiStatus.Internal
     public void initialize(String panelName) {
         this.panelName = panelName;
-        this.syncHandlers.forEach((mapKey, syncHandler) -> syncHandler.init(mapKey, this));
+        var snapshotKeys = new ArrayList<>(this.syncHandlers.keySet());
+        for (var mapKey : snapshotKeys) {
+            var syncHandler = this.syncHandlers.get(mapKey);
+            if (syncHandler != null) {
+                syncHandler.init(mapKey, this);
+            }
+        }
         this.locked = true;
         this.init = true;
         this.subPanels.forEach((s, syncHandler) -> this.modularSyncManager.getMainPSM().registerPanelSyncHandler(s, syncHandler));