Creating a bug for this from Slack conversation, which began with https://twitter.com/MairJulian/status/908084957368733696/photo/1. I know that this was originally fixed in 54 (bug 1341349), but before I mark it as a regression, I want to know what part of this pref/pingsender relationship broke. (Also: not sure this is the right component, but I know gsvelto is the first person to ask.)
It might be also worth looking into sending setting up an DNS name like crashsstats.telemetry.mozilla.org or even crashsubmissions.mozilla.org (if we want to avoid the word telemetry in it all together) which pingsender submits crash reports to, so that people are not confused on what pingsender does in this case. Initially that DNS name could simply be an alias pointing to incoming.telemetry.mozilla.org for now (and could point to something else later if needed). Let me know if I should open a new bug for this suggestion.
I've checked the content/plugin crash reporting patch on today's nightly build and the prefs are honored as expected. Turning off the "Allow Nightly to send technical and interaction data to Mozilla" checkbox in the prefs prevents any crash pings from being sent, as expected.
I forgot something: I've also checked that the crashreporter client doesn't send a crash ping in the same scenario described above.
Nils -- sounds good, please do.