bug When going to a link in my comment history (see link), I see a few replies. Only when I click the link to show all comments do all children for that thread show under the final rendered reply (as of this moment, 2 replies).

Noted, it's indeed a bug. I've sworn to never touch the comments code for the rest of the decade but I can make an exception this one time, please create a ticket on the bug tracker

All children of that thread should be noted, I would think.

I don't get notifications whenever you reply to my comments, I usually just see them by looking at the threads.