NOTE: does not work in single player

I managed to respawn in hardcore mode. I was playing in a hardcore world, with another player (they created the world) and got killed. I switched to spectate, then left to install shaders. I rejoined and was back in hardcore, able to have a second chance.

When I rejoined, I expected to still be dead, in spectator.

What happened was, I was back alive in Hardcore

Steps to reproduce:

Create a new world and set the game mode to Hardcore.

Get a friend to join

Kill your friend, then tell them to switch to spectate.

Tell them to leave the world, then rejoin

They should be in spectator mode, but instead are in Hardcore, which defeats the point of no respawns.