Magnetic catches can be too weak to work effectively on bifold doors, this means that the wind can easily blow them shut. In this video I replace some magnetic door catches with some catchstop door catches from Doorstopworld, which use powerful N52 Neodymium magnets. When replacing the magnetic catches, I also realised that the back plates had been installed with the anti-rotational grub screw pointing in the wrong direction, which created a gap. The gap was closed considerably by rotating the back plate by 180 degrees.
I got the stronger magnetic catches from this website- http://www.doorstopworld.com/catchstop.html
(I’m not on commission or an affiliate)