I tried it in terminal and it still shows blank buffer until I switch to
the buffer and press up.

emacs -q -nw -mm -l test.el

even when I switch-to-buffer from the other window, to make it open on both
splits, it appears empty

point is on point-max, and on line 74
last text is on line 73
line 74 has just one white space char
point-max is on first line of buffer, mode-line says line 74