In Qt applications using the QPlastique style under Ubuntu 10.04, tooltip text is the same color as the tooltip's background. This occurs when using the default theme, Ambiance. QPlastique style uses the text font setting (white by default) from the OS (Accessed by going to System -> Preferences -> Appearance and clicking "Customize"), but ignores the OS's tooltip background color setting (black by default). This results in a white tooltip with white border and white text.