While the file name mentioned often appears on third-party download sites like vfxmed.com , the tool is officially developed and maintained on platforms like Superhive (formerly Blender Market), where users are encouraged to support the developer for future updates. Ghostool - Superhive (formerly Blender Market)

It is primarily used by animators to visualize timing and spacing by generating static mesh references from specific frames of an animation. Key Features

(v1.0.2) is a specialized animation add-on for Blender designed to create "ghosts" or onion skins directly in the 3D viewport.

: Creates static "ghost" versions of your animated meshes at chosen points in time, allowing you to see the previous and next poses simultaneously.