When respawning the Ender Dragon, a couple of generated End Crystals are indestructible; they seem to be permanently in their "respawning the Ender Dragon" phase, with their healing beams pointed towards the sky.

This is rather frustrating because even though they're in an indestructible state, they still heal the dragon, leaving me stuck in the End with the only means of escape being death. I realize that I can still kill it even when there're crystals, but this is not an easy task.

Is there a workaround? Exiting and reloading doesn't work. This is a very annoying problem. I know that indestructible crystals can be disposed of by using them to respawn the Ender Dragon, but that's not a viable workaround until I get rid of the current dragon.