The neptune-ui is using the Font.Light weight everywhere in the UI. This works fine for normal latin characters as they are included in the "Source Sans Pro" font.

For arabic glyhps, the system needs to find a font which supports arabic characters using the "light" weight, which currently doesn't exist and it falls back to render invalid glyphs.

This is currently the case in the virtual keyboard and the i18ndemo.

To fix this we need to install an font into the system which supports this e.g. FreeMono.ttf