JSZip Changes Contents of Files (pdf) While Decompressing

I'm using the FileReader api to load the contents of a file input into the browser's memory. This jsfiddle includes a working example: https://jsfiddle.net/qyh1s60d/

I turn the result into a Uint8Array and display it in a div:

<label for="file-pdf">select a pdf:</label>
<input type="file" id="file-pdf" name="files[]" />
<div id="result-pdf">
</div>

JS

document.getElementById('file-pdf').addEventListener('change', handlePdfSelect, false);
function handlePdfSelect(evt) {
    var files = evt.target.files; // FileList object
    var reader = new FileReader();
    reader.onload = (e)=>{
       var res = new Uint8Array(e.target.result);
       resultPdf.innerHTML = res.slice(0, 5)
    }

    reader.readAsArrayBuffer(files[0]);

  }

So far so good. The div displays an array of numbers as expected.

Next I want to use JSZip to get the same pdf located inside of a zip file. Here's the html:

label for="file-zip">select a zip:</label>
<input type="file" id="file-zip" name="files[]" />
<div id="result-zip">
</div>

And JS

document.getElementById('file-zip').addEventListener('change', handleZipSelect, false); 

function handleZipSelect(evt) {
    var files = evt.target.files; // FileList object
    var reader = new FileReader();
    reader.onload = (e)=>{
       var res = new Uint8Array(e.target.result);
       JSZip.loadAsync(res).then(function(data){
       var pdfs = []       
        Object.keys(data['files']).forEach(f => {
                         if(/\.pdf$/.test(f)){
                             pdfs.push(data['files'][f])
                         }
        })
        var pdfcontents = pdfs[0]['_data']['compressedContent'].slice(0, 5)
        resultZip.innerHTML = pdfcontents;

       })

    }

    reader.readAsArrayBuffer(files[0]);


  }

Even though I use the same pdf in these two file uploads, I get different Uint8Arrays displayed in the browser. Can anyone tell me why these are different, and how I can get the pdf data taken from the zip file to look the same as when it is directly uploaded as pdf?

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