I noticed they never try to get down from the couch, and this gave me the idea to raise their playpens up off the floor about the same height. So this is an elevated platform, about 18 inches or half a meter high. It makes the playpen more accessible.
I've never had one try to get out or fall, and our mouse also stays in his, carefully skirting the boundary.
So it's not without risk, but we have a good safety track record.
