Hi, while i did not have a need for it yet, i noticed the method "setOnClick" of ISButton to take the function and up to 4 parameters for the on click function.
Issue is, that it seems to set the button's onClick parameters (arguments/args) to arg1, arg2, arg3, arg3 instead of arg1, arg2, arg3, arg4.
File containing it: media / lua / client / ISUI / ISButton.lua , line #387
It is from what I've seen currently not used by the base game (with up to 4 args that is) and as such should not cause any issue regarding base functionality.
Thank you for your work!