This light-blocker is to be used with this interface, the -5mm version of the interface: https://www.thingiverse.com/thing:6277086
I have modified it with extended forehead-cap here, which you can use also:
https://www.printables.com/model/787545-quest-pro-style-meta-quest-3-face-cover
EDIT: I made a brand new from scratch
Video example: https://i.imgur.com/KqlVlhK.mp4
**OLD**
It's a remix of Chefschweisser lightblocker, originally made for the Quest Pro. But I had to almost totally remake it in order for it to fit the Quest 3, so it's almost entirely new. I made a notch that can be nudged under the interface on both sides, so that it fits the Quest 3, aswell as total structural makeover for it to be fit when having your face extremely close to the lense.
**/OLD**
The author marked this model as their own original creation.