https://github.com/void256/nifty-gui/commit/4fcf4fc95bea1ca1f7ea9bcefef8fc135ed23f61
It seems this bug still exists in nifty 1.3.3.
@void256 said: I have good and bad news :)<br /> <br /> The good news is:<br /> You've done everything correctly.<br /> <br /> The bad news is:<br /> Nifty has a bug where it is possible that an already applied style was applied a second time. This occurs especially when an ElementType is being copied. This is happening inside of the ListBox when the template element is copied for the visible entries in the ListBox. You'll end up with all effects applied twice to the element.<br /> <br /> So in case of the Hint effect you really have two Hint effects unfortunatly. As a hackish work-around you could modify both hint effects - but don't tell anyone that I've told you because this is really ugly :)<br /> <br /> I've fixed the problem for Nifty 1.3.2-SNAPSHOT. So if you're using a cutting edge Nifty nightly build it should work as expected.<br /> <br /> Thanks for being persistent ;)
Since this is over 2 years old, may I ask for a SSCCE reproducing the issue and eventually creating a bug report / issue on github for Nifty: https://github.com/void256/nifty-gui/issues ? Thank you! 