I stumbled across this claim pretty often in the last few years.
Now the problem is that I wasn't able to reproduce it but maybe it was just because I rarely visit tall buildings with multiple floors (Or I did something completely wrong, which I doubt because you just have to hold down 2 buttons).
Often you also find claims that this trick works with absolutely every elevator worldwide. Now my question:
Does it work? And if yes, are there any exceptions/limitations to it?