Why isn't alert message being printed?

I am currently applying for an Internship Internship Link

One of the things that I noticed right away is that you click on upload cover letter or paste cover letter, you're redirected to the home page of the job invite site Job Invite and sadly you can't upload your cover letter. On the other hand, the upload resume works perfectly fine but paste resume has the same issue.

Does anyone know how to resolve this issue and and be able to submit a cover letter?

I am not a web guru but since I am applying for an engineering position, I am trying to find a way around this. I right clicked the upload cover letter link and inspected the link with the inspect element tool. I found that this function

onclick="jvAddAttachment2('jvcoverletter', 'qLY9Vfwx')

was going to get called when the button is clicked. Now going into the JavaScript file for this html page, Inspect Element -> Sources -> *careers_8.js?v=303, I tried to do a basic alert statement, from alert dialog, to do some debugging to see what the issue is. Here's the code now

function jvAddAttachment2(id, companyId){
    alert("I got here");
    ....
}

I then did control s and the Inspect Element console outputted "Recompilation and update succeeded." so I am assuming the JavaScript file has been updated. However when I click the link(via right click, open new window), no alert box shows up.

Does anyone know how to get the alert dialog to show up? I think I've done as much as I can with my working knowledge from one web development course haha.