atrxi

FK/IK Snapping Tools is a Blender add-on by atrxi that snaps FK controls to IK and vice versa while animating humanoid rigs. It works on a variety of rig types and snaps in one click.

Smart Selection Propagation is a Blender add-on for topology-based selection of geometrically similar mesh elements by vector features. It selects repeating elements that need not be identical, matching geometry with slight variations, and similar islands.