Question

I want to execute another function when a button on a website is clicked. I wonder to know if this is possible with chrome extension functionality and is this ethical to make and it’s good to know that the code that I execute with my extension has many additions to the same website code?

Answer 1

To do this just add an event listener to the element you try to manipulate in your content script:

document.querySelector('#button').addEventListener('click', function(evt) {
   evt.preventDefault(); // prevent default action of the button
   otherStuff();
}

Also don’t forget to add this content script to your manifest.json

If it fits the purpose of the extension it’s ethical of course, therefore we have JavaScript :).