I can't remember where the option is in Mala, but look for "selected game line height" or something similar. This problem happens when the font's descenders (the 'tails' of letters like g, y, etc) are out of the bounds of the line height. Try making the line height greater or reducing the font size for selected game, that should do the trick. Let me know if you still have problems and I'll look at the Mala editor to find the correct option.