Most modern desks and chairs are too high for shorter people like myself (5'6"). This leads to the need for somewhere to rest the feet while working at an office desk. The problem with footrests is that they are a separate item from the chair, which becomes an issue as they don't fit in between the chair's legs and also get out of position or in the way when stepping out of the chair for a break.
Design a footrest that is attached to the chair's legs that has casters to roll with the chair so that it is never out of position or in the way of the chair's movement.
Fig. 1 CAD mold model (#1) that attaches to the chair's leg and has a flat surface to hold a wood slab. Designed to fit around the chair's leg (#2).
Fig. 2 Fully assembled rolling footrest attached to the chair's leg.