Creative inventory is unresponsive and buggy

I have not tested this with Survival but the inventory screen in Creative mode is very, very broken. It's extremely difficult to move items around and to place them where I want them to go. I can't shift-click anything. I can't just click on something to pick it up; I have to click on it and drag it around for anything to happen. It is extremely unresponsive, to a point that it is unplayable.