App platform worker hangs, sometimes giving exit code 12

We have a Laravel queue worker that is running fine most of the time, however sometimes it hangs. It doesn’t pick up new jobs, and it’s not responsive at all also not possible to login via Console to have a look at what’s happening. The CPU and Memory insights are low, on usual levels. Also it can’t really be something in the queue jobs, it always seems to finish the queue job at hand but simply doesn’t pick up a new one.

We might have to rework our application architecture to accommodate this, but first this question:

In the crash logs (via doctl apps logs <ID> --type=run-restarted) we sometimes do see container exited with exit code 12. I searched but can’t figure out what this exit code 12 means.