The panel measured itself once, a fixed delay into the keyboard's animation,
so it landed against a viewport that was still moving - and in a sidedock
drawer no resize event fires at all, so it never moved. It now re-places every
frame until its own position holds still, which needs neither a duration to
guess nor an event to wait for. Its input taking focus is another trigger:
that is what opens the keyboard in the first place.
The preview had no viewport meta, so a 390px window still laid out at 980px:
every "mobile" screenshot was a desktop one at a phone's aspect, and
coarse-pointer rules could not apply. Which is why the tap targets looked
fine here and were not.
hh