Move by dragging item is not supported (Blender 5.0 and later)

This add-on's shape key menu is unique and replaces the default menu.

As a result, the new shape key menu changes in Blender 5.0 are not reflected.

Solution

Disabling "Use Folder in List Menu" in Add-on Settings will disable menu replacement in the Property Editor.
In that case, access the add-on's functions from the side menu (N) in the 3D view.

The multiple selection feature is implemented in a unique way in this add-on, so please use that.

important point

The shape key for the folder is the same shape key data as the normal shape key.
The data for the folder is stored in the vertex group options.

(Since it is a specification that custom properties cannot be added to the shape key, it is implemented like this)

List filters are not available

• 
  
• The Sort by Name option and the Folders feature in the search menu at the bottom of the list cannot coexist, so enabling them will ignore folding and sorting.

others

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• The batch move function within a folder is heavy when there are many items.
  • (Because the standard operator can only be used to sort the shape keys)