After the pocket for dogs up to 10 kg and a size L was described, I have back rätselnd and hergewendet and considered how well the dog is as fit. Mine is 5 months old and weighs only 5.6 kg, far from the limit removed, but I had to fold it well before it would fit there. For Chihuahuas might well suited in size, no idea why the case is referred to as L.
Too bad with the return after a very long waiting period (for which the seller may not, but the inches), especially as the bag itself is really pretty and practical and also seems to be ok from a processing perspective.