Dmesg doesn’t go back very far, does it? I only see the current boot and the one before that, which was a normal shutdown.

I believe I was able to see the last logs before the system turned off last time, and the last messages were syncing discs and all buffers synced, which I would have expected to be part of a normal shutdown.

If it happens again I’ll be sure to get the logs before the crash or shut down and save it to a file.