Note that, in the :applications key value I shared just earlier, I’d already removed the :logger_logstash_backend as @axelson suggested. It didn’t seem to affect the errors. It definitely seems like, because that backend isn’t an Elixir application, it shouldn’t be included anyways, but it also definitely seems like Logger itself is starting the GenServer (or similar) for that backend directly.
I’d previously thought about trying to configure the backend later in the application startup, e.g. via a new application ‘start phase’, but Logger seems to require all backends to be configured at compile time so that doesn’t seem like a possible solution.
