Prevent "Fit to Window" setting I have the following image and when I click on  it. it will pop out into a colorbox modal, but it currently re-sizes it to fit to the window. How would I just resize it up to only the width of the window and have the user scroll down to see the rest of the image?

I'm using the colorbox module. I know I have to unset the innerHeight to auto or something. But how would you override a javascript snippet without affecting other pages on the site?
You can try with below Jquery snippet.

(function ($) {
var cboxOptions = {
     width: '95%',
     height: '95%',
     maxWidth: '768px',
     maxHeight: '768px',
}

$('#colorbox').colorbox(cboxOptions);

$(window).resize(function(){
   $.colorbox.resize({
     width: window.innerWidth &gt; parseInt(cboxOptions.maxWidth) ? cboxOptions.maxWidth : cboxOptions.width,
         height: window.innerHeight &gt; parseInt(cboxOptions.maxHeight) ? cboxOptions.maxHeight : cboxOptions.height
   });
});