Function newest_timed_from_others 

pub(crate) fn newest_timed_from_others(p: &Posted, extra: &Extra) -> i64

When the newest message of others in a notification was sent (ms), by its messages’ own times only; 0 when they give none: a notification’s own time moves with a silent repost, and is never taken for a message’s (replies::check, a reply crossing their newer messages).