Ikea Vilmar spacer/shim for stability improvement

I have some one old Ikea Vilmar chairs that lack shims to stabilize the seat. 

I create this model that fits above the legs, between the seat and the leg, to give stability to the seat while you lean on it. Print four, one for each corner and slide them until you cant slide them more

Design by sudoeste on MakerWorld (license: CC0).