After patch 1.16, a macro in execution cannot be interrupted anymore. Before, you could do it by pressing again the same macro or another one.
This is very annoying, since for example, if I have a macro with 10 /equip "xxx", I have to wait all 10 equips (even if I need, for example, only to change the first 2) before executing another macro.
I hope it's a bug, and not a real "fix".