Made a under desk mount for the Flex mini. One where it won't move and will stay secured to the desk. i guess you could also wall mount it or even floor mount it if you so please.

Designed to be printed with no suppports.
Printed mine with Polymaker Polyterra PLA on a P1S. 
standard 0.2mm profile but with 3 walls and 4 bottom layers.
max Screw head is 8mm and shank 4mm

.f3d .3mf and .stl files are available to download