Summary

This is my take for a drop ceiling cable hanger. It is designed to attach 7.5mm (0.3") cable to a 25mm (1") drop ceiling rail.
It takes two parts for every hang point. Simply fit the two over the cable and the rail edges while they are a few cm apart, then slide them along the rail and the cable until they lock.
To release, slide the two parts away from each other.

The part is printed with a brim, standing on its flat end for best strength.

Oops.. Just realized I uploaded the wrong stl file. Now (21/3/22) the correct file is up.