0.14.0 Windows 10 Edition.
I noticed that placing containers whilst flying only results in opening the containers' GUI, even when holding Shift and Space simultaneously.
What should happen:
Holding shift should allow placement of containers on top of another without opening the containers' GUI. When flying, usually you need to hold shift and space to do this.
What Actually Happens:
You need to be standing on a block in order to shift+place another container without opening GUI, which is awkward in a tall build.