More than 2 pages per row does not work

Hi, I added the following line in my zathurarc :

set pages-per-row 3

It does not work, I have only 2 pages per row when I use toggle_page_mode (with the appropriate keybinding).

zathura 0.4.3 girara 0.3.2 (runtime: 0.3.2) (plugin) pdf-poppler (0.2.9) (/usr/lib/i386-linux-gnu/zathura/libpdf-poppler.so) Debian GNU/Linux buster (updated)