Material Slots Cleaner evaluates selected meshes and removes any material slots that are not actively assigned to geometry. This tool addresses the common issue encountered when separating imported assets, such as FBX files, into multiple pieces. By default in Blender, separated meshes inherit all material slots from the original object, even if they no longer use those materials. This add-on automates the removal of these empty slots across multiple objects simultaneously. It specifically targets the object material slots rather than purging unused material data blocks from the overall blend file.