I am not sure if this is intended, but I saw it in a YouTube video and thought I'd report it here. Basically, when you sleep in a bed and you place a boat where your valid spawn point would be plus some blocks above it, your respawn point seems to be shifted upwards until you can spawn somewhere. I am not sure if this is intended respawn behavior or not, so I am asking here. Shown below will be a setup on how to recreate it. Sleep in the bed, row your boat into the corner, and then /kill yourself. You should respawn on top of the tall glass pillar. If this is an unintended trick, then it's a pretty cool one