The list was built oldest-first and then scrolled to the end, so opening a
session started at the top and raced downward through everything in it. On
an imported conversation that is nine hundred items measured before a word
is readable, and it was visible every single time.
Laying the list out from the bottom removes the journey rather than hiding
it. The newest message is index 0, so the first frame is already the right
one, and older items are composed only when somebody scrolls back to them
-- which is also what makes a long history cheap rather than something to
load up front.
Following the tail gets simpler as a result. There is no longer a moment
where new content pushes the anchor away, so "am I pinned" is read
straight from the scroll position instead of being remembered across
scrolls, and a new message is one step back to index 0 rather than a jump
across the transcript.
Checked on the 863-event import of this very conversation: a screenshot
one second after opening is already at the newest message, and scrolling
back reaches older ones in the order they happened.
iris
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