So my female budgie often sleeps like this. I cannot imagine how this could be classified as comfortable. As you can see from the photos she climbes to the ceiling of the cage and spreads her legs attaching one to the side of the cage and one to the ceiling. So bizarre! She doesn't look sick, chirps, flirts with it's mate, eats, flies as usual, cleans it's feathers daily, breathes normally, poops normally. There also is no lump on the tummy to indicate that she is trying but cannot lay eggs.
Pray for my budgie, I guess there is nothing wrong with her she is just a weirdo 😂