You can not worry about such seedlings.

With a successful set of circumstances, tomato seedlings from the first days of landing should stand on the windowsill and get used to the ultraviolet light. You can not worry about such seedlings. If light pigments appeared, then, of course, the missing leaves cannot be returned. Such tomato sprouts will lag behind in development. Fighting white spots that arose from a sunburn can be in several ways, namely: