How to find out what makes Home Assisant crash regularly

Hey there!

Since a couple of weeks Home Assistant (running on a Pi3 B+) keeps crashing about once a day - usually at night, but lately also during the day. I have to do a hard reset to make it run again.

I don’t know which logs I could look at to figure out what is causing this - I don’t recall changing anything else than converting Automations to Node Red flows - no Idea how this could be an issue.

I looked under Supervisor>System>System Log, but this only shows what happens since the last boot and no issues.

Where else could I look? I really don’t want to set up everything from scratch… (even with backups, as long as I don’t know the cause, it probably isn’t a good Idea to simply recover a potentially broken backup)