XPStyle has a map HashMap<Skin, Border> borderMap. Skin has a field
Component. This map is never cleaned. Thus there is reported memory
Skin is used for very short period of time. It should be created only
when needed and discarded as soon as we done with it. Only one field
from Skin is used to hashCode() and equals(). This field is Skin.string.
I suggest to change borderMap to HashMap<String, Border> and use
skin.string as a key instead of the skin.