Corner Dust Guard for Steps, Dust Proof Guard, Stair Corner Dust Guard, Dust Corner Protector for Furniture and for Home Wall Edges - Etsy UK
Decorative Star Dust Corner for Stair Steps With Bronze Finish - Etsy UK
Stair dust corners introduced at the end of the 19th century to make sweeping easier. They keep dust from accumulating in the corners : r/Damnthatsinteresting