TLDR; Fixes your handbrake button on Skoda Octavia (and maybe other VAG cars) if it popped off, and won't stay back on.
(Updated 2024-07-04. User gon on the below forum informed me that the tip was 1.5mm too long. I've removed 1.2mm, and hope that it works straight out of the printer now. Please leave a comment here on printables if it worked for you, or if it needed modifications. It's worked in my car now for 7 months)
As pointed out by lex131 on https://www.briskoda.net/forums/topic/459408-handbrake-button-came-off/?do=findComment&comment=5334867 the handbrake button can pop off due to wear of a small hook mechanism.
Before you attempt this fix, the first step is to check to make sure your hand brake actually works and the only problem is the silver plastic button that popped off.
See above briskoda comment by lex for how the mechanism works, and where to insert this bit. I designed this 3d model from his sketches, and installed it on my own loose button. It has worked every since (for 4 months now, knock on wood).
Print sideways with snug supports with no interface layers in the small gap
The author marked this model as their own original creation.