I’m guessing this judge considers the telephone to be an example of negligent design as well. After all, the phone company doesn’t record every phone call I make and disconnect me if I mention an illegal drug.

Before you go through a bunch of calibration, I’d see if it happens with a different filament. Those black particles there are likely something with a higher melting point than the surrounding PLA, otherwise they’d “smear” during printing. I’m betting you’re hitting some intermittent clogs. See if the problem happens with a single color filament.

I like to do things just off the top of the hour, since top of the hour is when many maintenance crons run. If you’re running a modern cron daemon, you can rewrite that as:

3 1-23/6 * * * docker container restart lemmy-lemmy-1

https://crontab.guru/#3_1/6_*_*_*