This seems to be LWJGL related.
First: Some uses of "control" now seem to be mapped to "apple/command". This sort-of makes sense. Microsoft windows uses ctrl-C for copy, ctrl-v for paste; Apple uses command-C for copy, command-V for paste, etc. So, the LWJGL seems to be mapping ctrl to command in many/most cases.
Ctrl-"drop" drops a stack on windows.
Command-"drop" drops it on the mac.
(... is there any other use of control in vanilla?)
In fact, I just found another issue here. After command-"drop" (I have "drop" bound to a key; this might be different on a mouse), the "drop" key does not work once. I have to press it once to "clear" it, before it is seen to work again.
When starting up, I normally find the "command" key stuck – the first time I try to use it, it does not work. Additionally, any time I use command-tab to switch to another app, and then back, it is stuck again.
(This is not all cases. I can map a keystroke command to "control", and it still works. Optifine, for example, maps zoom to control by default (I remapped it to Z before testing.))
Linked issues
Comments 2
Yes, this is more MC-3643
While the issue with ctrl-drop versus command-drop is a duplicate of the other tickets, the issue with the command key being "stuck" is not.
> When starting up, I normally find the "command" key stuck – the first time I try to use it, it does not work. Additionally, any time I use command-tab to switch to another app, and then back, it is stuck again.
That issue is not referenced, that I saw, in any of the other reports.
It affects me because I normally find it when I attempt to drop something and it won't behave, or if I'm trying in chat, and I try to backspace to fix a typo only to find that I've wiped out almost everything that I've typed.
Near as I can tell after playing with this for 2+ weeks now, Minecraft never sees the key_up on command in some cases – including command-tab out of minecraft. Even command-tabbing back into minecraft will generally not see the key_up.
That it starts misbehaved ... still confuses me. I'm not sure if command-tab is the only source of lost key_up notices.