Stackableshulkerboxes can not be used mormally in version 1.21 and above

[AbroadSphere]

When you set it to be true, shulkerboxes will be stacked automaticly in contianers

[AbroadSphere]

My English is poor ,hope you can understand what I mean

[WinExp]

你可以使用 “Stackable Shulker Fix” 模组来修复此问题（锂模组0.14更改了包名，你可以下载github actions构建的版本）
You can use the "Stackable Shulker Fix" mod to fix the problem (Lithium mod 0.14 changed the package name, you can download the github actions build)