i spent the past five hours trying to set up crash reporting to an alternative Breakpad server implementation (tried simple-breakpad-server and mini-breakpad-server). Unfortunately, without any luck whatsoever.
Crash reports are neither written to the database nor does a link show up in the web UI.
Set the crash reporting URL inside about:config, as it should be. Other software (electron apps in particular) reports just fine.
Does Firefox not support other Breakpad solutions outside Socorro?
EDIT: Turns out I had to set MOZ_CRASHREPORTER_URL, as well. Unfortunately, that doesn’t really change the situation. Now it just complains about not being able to send the crash report, at all. I suspect that’s due to the “extra” files that other Breakpad servers/APIs wouldn’t know about.