So I was on my server just building something and I wasn't using shaders (because lighting can mess with where I can see the ghost brick sometimes). I wanted to see how the build looked so far with shaders on, I turned shaders on high and looked at the build, then I turned shaders back off.
Then this happened,
after a few seconds, Blockland crashed. I restarted Blockland and it didn't occur again even after switching between off and high shaders.
Strange though, and I didn't save the console.log.