The ptyxis window seems to have a noticeable margin on the left and
right, making fewer columns of text visible compared to gnome-terminal
with the same font.

Control: forwarded -1 https://gitlab.gnome.org/chergert/ptyxis/-/issues/128

The ptyxis maintainer is particularly concerned about performance. For
instance, screen reader support is currently disabled by default
because of its performance impact (although Debian and Fedora are
overriding that).

See https://gitlab.gnome.org/chergert/ptyxis/-/commit/dce364aa36861
where this has been acknowledged as an issue and a hidden preference
has been added to disable the extra padding. By hidden, I mean it's
only accessible via gsettings instead of the preferences dialog. I
have now set this bug's forwarded link to a related upstream issue
that has been closed.

Thank you,
Jeremy Bícha

Fair enough. A hidden preference seems sufficient for this.

I hope that in the future it might be possible to achieve good
performance without padding, but having a preference to prioritize zero
padding even if there's a performance penalty seems like the right
tradeoff here.