…logged events it all stopped on the container boundary: only with luck you'd get a proper backtrace, but you usually didn't because the coredump processor on the host couldn't deal with the different compiler/debug situation inside the container. Given that containers are mildly successful these days this of course is a big problem.
Back in v255 we added a new unit file setting CoredumpReceive= to unit files (services and scopes in particular), to address this issue.