I am translating GanttProject in Hindi language. Though it is displaying in Hindi perfectly at some places only, and at most places in Desktop application(Windows 11) it is displaying blank boxes (not rendering Hindi characters). English interface is normal.
You need to choose the application font which includes Hindi glyphs. Edit > Settings > Application UI > Application font
Thanks. It is working with Mangal font.
I had changed earlier only base chart font, not the Application font.