I have a baby jumper that hangs from a door frame. It's in good condition and works fine.
The only issue is that when I got it second hand, it was missing a small metal rod (like the one pictured) that helps secure the padding to the plastic, so I used string to tie it instead. The padding is also secured on by another metal rod and multiple Velcro strips. As I said, I used string in place of the rod and it felt completely secure and I never had an issue. If you want to be extra cautious, you could probably find a metal rod to replace it.
Baby jumper (Montgomery and San Mateo)
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