tintin++ mud client #split function does not work (anymore?) - on iPadOS 15

[fal3nsh]

Hi there,
We found a potential bug in ish when handling some tintin++ (mud client) feature in handling "split" lines/zones on-screen (tmux alike) when playing a VT100 text mud 👍 (scandum/tintin#77).
tintin++ dev says it used to work properly on ish as well !
But now, the split zones and line drawings are handled and displayed at first by ish running tintin++, but whenever some line is received from mud or from input, the fixed splits vanish and start to scroll up as well as all text on screen. Such functions (split lines and buffered zones) do work smoothly on other terms.
Any recent change on ish could have led to this ?
Thank you for support.