Hello!

I currently do most of my freelance work at a library because working from my tiny apartment sometimes drives me bonkers. Unfortunately the chairs here are ancient and have super deep seats - I have a monitor lift for my laptop etc, but I have to sit on nearly the edge of the seat with no back support, and am finding myself in pain by the end of the day.

Tragically I can't bring a full-on proper chair into the library every day - does anyone know of any portable lumbar cushions that are more free-standing? These aren't traditional office chairs - they look like if a wide square armchair and a traditional wooden school chair had a baby, very boxy and wide. A straight-up lumbar cushion would just slip out the hole in the back where my lower back would rest, so I'm looking for something that's actually connected to a seat/cushion as well that could somehow hold it in place. It doesn't have to stand up on its own, I could prop it up against the back of the chair - just need something connected to a cushion I'm sitting on!

TLDR: looking for portable back-support that is connected to a seat cushion for a weirdly shaped library chair, almost like a portable carseat or something

Thanks!