I was on my realm and going to craft some more rockets because our rocket storage was getting low and like usual, i fill up my inventory completely of the recipe items because on Win10 you can Shift + Click items and they will just be thrown to the ground. Instead, when i tried to craft some rockets, one of the stacks becomes attached to my cursor and no matter what UI I use, its stuck there and i can move items, drop the glitched stack, cant do anything in any UI until i relog. i made a video but it was too large to post here. 
Use this link