one of the java fern started to sprout new leaves from the rhizome... but
instead of that paper-opaque bright green, it is much darker green at the
tips, almost like what you would see if you smush the lettuce leaf and
damage the cellls (somewhat translucent, but not really.. just looks
darker), or soak a green paper in water. the shape of the new leaves look
normal (meaning, doesn't look deformed, or curled up or anything).. just
almost two-tone.


That's normal. I'm not sure whether it specifically means the plant is
healthy, or if it doesn't mean anything at all.

Best regards,
Bob