scroll down on-sent missing sometimes

[r10s]

when the message view is already scrolled down completel, sending a new message does not scroll down.

cave: for incoming messages we want to scroll down only if already scrolled down - otherwise the scrolling position should stay as is (otherwise it is hard to read old messages in a chatty chat)

Seems to happen with stickers.

[r10s]

ftr: to reproduce, open a somehow filled "Saved Messages" and send sth. as "hi" (in the video, scroll down happens only when tapping the corresponding button);

RPReplay_Final1720693374.MP4

[r10s]

it is happening again on current master :/

(the last visible message with the text "3" only became visible after manual scrolling)

for reproducing: it happens quite often, but not always ...

RPReplay_Final1722716324.mov

[zeitschlag]

Will close and create a new issue ➡️ #2260