Even though the universal USB-C chargers were a step forward I miss the Lenovo USB-A type charger plugs. They stayed inserted. On the contrary, small movements of the PC easily cause USB-C plugs to slip fully or partly out. This holder is pushed on to the laptop, in this case a Lenovo Thinkpad T490 and effectively keeps the plug in place.

I used OpenScad to design the holder and by changing parameters it may be adjusted to fit other laptops. See below for the design and STL files.