When does this happen?
`inReplyTo` just links to the immediately prior message, so if your instance didn't get B, it has no way to link A and C. Do instances seriously implement user-level blocks/mutes by doing something like this in the UI, or am I missing some other situation when this behaviour would make some sense?
@lauren If you notice it happening in the future on publicly-viewable messages, I'd appreciate a heads up so that I can see if there's anything I wouldn't expect about the messages.
@robryk Judging from reports (and my own experiences) there are a number of ways this happens in modes where it's nonobvious that something is missing. I do not understand the protocol well enough to divine the details.