DIY fix broken chair backrest

We have this old 5yr-old Carrefour chair with it's backrest broken at home, still keep it as a leverage to fetch things from higher cupboard/wardrobe at home. To restore it's functionality i try to diy a short term fix to it.

I'm no spider, so no fancy webbing patterns here.I just do some simple criss-cross knots across the frame. The idea is to create a frame to place a small pillow as the replacement back rest. We have this ball of strings sitting around, can't remember where we got them from.

An old T-shirt to re-cycle as the cover. See the little pillow underneath it.

Once done, place the pillow at the backrest/knotted area, let it 'sit' on the bottom part of the knots. Then slip the T-shirt on to act as cover. Pull the rest of the excess part behind, twist & tie it with a string. Bundle & twist it inwards to make it look neat.

Here is the end product. Tried & feels quite comfy but not sure how long it can last though.

 Front

Back

After cleaning up this little room on 2nd floor, i think its ready to be a study room.