fixup for shift support

src/inventoryWindows.ts

@@ -15,9 +15,7 @@ import BeaconGui from 'minecraft-assets/minecraft-assets/data/1.17.1/gui/contain
 import WidgetsGui from 'minecraft-assets/minecraft-assets/data/1.17.1/gui/widgets.png'
 
 import Dirt from 'minecraft-assets/minecraft-assets/data/1.17.1/blocks/dirt.png'
-import { subscribeKey } from 'valtio/utils'
-import MinecraftData, { RecipeItem } from 'minecraft-data'
-import { getVersion } from 'prismarine-viewer/viewer/lib/version'
+import { RecipeItem } from 'minecraft-data'
 import { versionToNumber } from 'prismarine-viewer/viewer/prepare/utils'
 import itemsPng from 'prismarine-viewer/public/textures/items.png'
 import itemsLegacyPng from 'prismarine-viewer/public/textures/items-legacy.png'
@@ -351,6 +349,13 @@ const mapSlots = (slots: Array<RenderSlot | Item | null>) => {
     try {
       const slotCustomProps = renderSlot(slot)
       Object.assign(slot, { ...slotCustomProps, displayName: ('nbt' in slot ? getItemName(slot) : undefined) ?? slot.displayName })
+      //@ts-expect-error
+      slot.toJSON = () => {
+        // Allow to serialize slot to JSON as minecraft-inventory-gui creates icon property as cache (recursively)
+        //@ts-expect-error
+        const { icon, ...rest } = slot
+        return rest
+      }
     } catch (err) {
       inGameError(err)
     }