I made some holders for LED-strips (width: 10 mm, thickness: about 2,5 mm). Those that are designed as clips don't use much force, i.e. they move easily. The others are either fastened to the wall with screws or using bolts in cupboards or shelves and the holes that are there to fix holders for boards. 
The wardrobe doors leave a small gap, so that even there the holders fit. 

Orientation during printing is choosen to avoid breaking the holders (i.e. strings along direction of forces)

printed using PLA

The various flavours are the following: 

• holders for shelves or cupboards
  • holder without hole to clip to a  shelf
  • holder without hole for the top of a wardrobe
  • holders with holes to fasten them in spare holes of wardrobe or shelf (the holes that are usually used for board holders), one with a bolt for the LED-controller
  • bolts to keep the holders in place
• Holders for walls
  • a long one, because there was already a hole in the wall that I wanted to use
  • another long one with the strip holder rotated
  • a short one
• Strip manufacturer: Dongguan D-Win Lighting Ltd.
• Strip distributor: Briloner