if you want to drop a whole stack, you have to do command+drop key shortcut, in order to do this with default, ie q, you have to hold down shift so it doesn't straight up quit minecraft, for mac, cntrl-key would work just fine, thank you, for instance, i set drop block to r, and if i hit cmd r once, it works, but i have to hit r a second time without command in order to drop another stack of something else, when hovering over blocks in my inventory, repeated cmd-r's work but when out of hot-bar, i have to hit r again to reset the ability to drop objects, and when i press r, even if i have another item selected in hot-bar, it wont drop anything until the second press of the key