Third party plugin issue due to contact form maker plugin

Hi,
I am developer of wordpress plugin. I want to point out one bad practice(maybe) in your code.
I am not able to figure out which file.
You are extending the native objects and modifying the behavior of Array class.
Further refrence –
https://stackoverflow.com/questions/14034180/why-is-extending-native-objects-a-bad-practice

So whenever other developer try to do this-

var myArray = [];
console.log(myArray);    // it should print empty array but it is not . It is printing the properties which were added by extending the object. 

It is adding _eachproperty

So it is really messing our plugin code.
For example –
if i try to loop inside array

for(var i in myArray){
console.log(i);   //it is giving unwanted properties along with its own properties. 
}

If you have any way to avoid it . Do recommend us.