Some mechanical nerdery for you: magazine safeties / disconnects sound good on paper, but in my view are dangerous and counterproductive, so should not be a thing. But they are. So here we are.

The Browning Hi Power GP35 has possibly the worst magazine safety ever devised, and this vid explains why, with reference to two other systems (SIG P210 P49 and FN 1910) which aren't so terrible.