Vertical chinese text can't display correctly when using WenQuanYi Zen Hei(wqy-zenhei.ttc) font

GIMP 2.10.8 added a feature to make text display vertically. However, this feature can use for only english and arabic numbers and not for chinese text and maybe other non-english text (I'm not sure, didn't test with other non-english text).If I use it with chinese text only result in mess and nothing more. Thank you.