because $.proxy returns a function, it can also be used like this:
`$.proxy(function, context)(argument1, argument2)`

Therefor my code failed the test. Added a conditional statement, now it's working again.
However `$.proxy(function, context, arg1, arg2, arg3)(arg4, arg5, arg6)` will only use arg1, arg2 and arg3, but this seems logical to me.