Edit
The standard piece has a 0.2 clearance in the carabinier, in my case it opens just fine after a little initial resitance, but I added 0.3 and 0.4 clearance versions in case the standard ones bind too much on different printers/settings.
The cut is angled to prevent the carabinier from opening from the inside, but of course, the tighter you can print it the better.
The author marked this model as their own original creation.