Fix data prep for self cyclical containers (#15112)

src/module/item/container/document.ts

@@ -51,11 +51,19 @@ class ContainerPF2e<TParent extends ActorPF2e | null = ActorPF2e | null> extends
  return super.bulk.plus(this.capacity.value.minus(this.bulkIgnored));
  }
 
+ override prepareBaseData(): void {
+ super.prepareBaseData();
+
+ // Simple measure to avoid self-recursive containers
+ if (this.system.containerId === this.id) {
+ this.system.containerId = null;
+ }
+ }
+
  /** Reload this container's contents following Actor embedded-document preparation */
  override prepareSiblingData(this: ContainerPF2e<ActorPF2e>): void {
  super.prepareSiblingData();
 
- if (this.system.containerId === this.id) this.system.containerId = null;
  this.contents = new Collection(
  this.actor.inventory.filter((i) => i.container?.id === this.id).map((item) => [item.id, item]),
  );