I'm trying to detect when my Chrome browser is finished loading a remote pdf, for instance from https://arxiv.org/pdf/2108.11353.pdf

The context is I'm working on a chrome extension and I'd like the content_script to execute some things only after the pdf is downloaded and displayed.

I'm open to using JQuery but

$(() => {})

is triggered too early and things like

window.addEventListener('load', function () {
    alert("Hello")
});

document.addEventListener("DOMContentLoaded", function(){
    alert("Hello")
});

Are not triggered at all