If you hold shift + space while in spectator mode, you float upwards in spectator mode.
Linked issues
Comments


Can reproduce, confirmed for 15w44b.

Can reproduce, always have been able to. I assume that the keyboard IS recognizing both keys, firstly because the shift key and other modifier keys should always be handled separately from other keys, and secondly because in the provided video the player stops rising as soon as it/he rises above the water.
Can't reproduce, might be your keyboard not recognizing both keys pressed at once.