I can confirm this happens on font.family: "Ubuntu", the default fallback font of Chinese seems to be "Droid Sans".
Here's the output of Qt.fontFamilies() on our Chinese image: qml: DejaVu Sans,DejaVu Sans Mono,DejaVu Serif,Droid Arabic Kufi,Droid Arabic Naskh,Droid Naskh Shift Alt,Droid Sans,Droid Sans Arabic,Droid Sans Armenian,Droid Sans Ethiopic,Droid Sans Fallback,Droid Sans Georgian,Droid Sans Hebrew,Droid Sans Japanese,Droid Sans Mono,Droid Serif,Liberation Mono,Liberation Sans,Liberation Sans Narrow,Liberation Serif,Lohit Devanagari,Monospace,NanumBarunGothic,NanumGothic,NanumMyeongjo,Sans Serif,Serif,Symbola,TakaoPGothic,Ubuntu,Ubuntu Condensed,Ubuntu Mono,文泉驿微米黑,文泉驿等宽微米黑 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1475205 Title: Random Chinese character missing with Ubuntu font To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1475205/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs