Run as root

cat <<EOF> /etc/dconf/profile/user
user-db:user
system-db:local
EOF

mkdir -p /etc/dconf/db/local.d/

cat <<EOF> /etc/dconf/db/local.d/00-hidpi
[org/gnome/mutter]
experimental-features=['scale-monitor-framebuffer']
EOF

mkdir -p /etc/dconf/db/locks
cat <<EOF> /etc/dconf/db/locks/hidpi
/org/gnome/mutter/experimental-features
EOF

dconf update && reboot

Source: https://wiki.archlinux.org/title/HiDPI#GNOME