In order for threading to work in email clients, the Message-ID header needs to be set on the initial email, with following emails having In-Reply-To / References set to that same Message-ID.

I can't reproduce this: mail threads properly in my client.

Also, damn, I've used libphutil for so many things - ExecFuture and HTTPSFuture are just by far the best thing out there for async work.

Actually, we can go one step further than D19686, I think.

We have a general initialization order issue where a later config file may define a load/--library setting that includes a typed Setting/Config object for a setting value in an earlier file. So I think this needs to happen in several phases:

T11934 is not exactly adjacent here, but I suspect it feeds into some other incidental goals and may provide a workaround for some things which get removed.

I'm looking toward making arc alias work in the general case again, but the big thing this is blocked by is reliance on config.

See T13098 and T13203.

I think we have no realistic way forward here. See T13201 for related things which are moving forward.

I don't currently plan to make "Disable User" any more granular than it is. If you have a use case where you want multiple administrator levels and to allow administrators at a certain level to act downward but not upward, you might be able to do something like have an enforcer-bot account which users can instruct to disable one another. The enforcer-bot itself could act via the API.