its sole purpose was to catch someone snooping through my laptop, (I mean in the same household)
That's why I
always lock my screen (set a shortcut if you don't have it yet) when I walk away. No matter how short, I don't get up before locking it.
I do the same - habit from past job where I had a little bit
strange collegue. Just for the record: this is not very secure solution, some lock screen in linux environment can by bypassed, don't know about other OSes. It is good to prevent children from play with your workstation, but if someone has enough time, it won't help.