INVALID_ACCESS_ERR when trying to render a pdf using PDF.js-Collection of common programming errors

I have an s3 bucket hidden behind an nginx proxy. If I try to view a PDF using that proxy, I get this error

XMLHttpRequest.responseType cannot be changed for synchronous HTTP(S) requests made from the window context.
Warning: Unhandled rejection: Error: INVALID_ACCESS_ERR: DOM Exception 15

But that same link downloads the file if I visit it from my browser.

This is my nginx configuration for the proxy_pass

location ~* ^/s3_redirect/(.*) {
    internal;

    set $full_url               http://$1?$query_string;
    set $s3_bucket              'my_bucket.s3.amazonaws.com';

    proxy_http_version          1.1;
    proxy_set_header            Host $s3_bucket;
    proxy_set_header            Authorization '';
    proxy_hide_header           x-amz-id-2;
    proxy_hide_header           x-amz-request-id;
    proxy_hide_header           ETag;
    proxy_hide_header           Last-Modified;
    proxy_ignore_headers        "Set-Cookie";
    proxy_buffering             off;
    proxy_intercept_errors      on;

    proxy_pass                  $full_url;
}

Using the s3 url instead of the proxy url, PDF.js works and correctly renders the file.

Can someone help me fix this?