One of the replies for
https://reddit.com/r/nethack/comments/za85y0/odd_appearance_and_behavior_of_nethackexe_on_win11/
might be relevant. Changing what seems to be a system-wide
setting for the benefit of one program feels a bit extreme though.
[I've tried to manually split the text into lines of reasonable length
segments after copy+paste on OSX turned it into one long line,
and I've left off attribution to the reddit user-id.]
" the new console is... so much more different, and makes all kinds
" of ascii things 'work' and breaks others in weird ways.
"
" Anyways search for 'Terminal Settings' under
" Privacy & Security -> For Developers and and change the terminal
" to 'Windows console host' and it ought to be like the 'good old terminal'.
It's actually
Settings -> Privacy & Security -> For developers -> Terminal
and you reach the same place by running nethack from Power Shell
and right clicking on the window title bar then picking Settings from
the popup menu.
I didn't see any change in behavior after trying that. Corridors using
the IBMgraphics checkerboard character were only visible adjacent
to the hero with the lit_corridors option On. Away from the hero, or
with that option Off, known corridors were invisible.
You can always switch to OPTIONS=symset:default to stick with
plain text. Or you might need to muck about with IBM-style "code
pages" and such, something I've never bothered to learn about.