A way to preview a local PDF?

I'm running into an issue where I cannot preview a local pdf.

I have tried:

 <script type="text/javascript">
    document.addEventListener("adobe_dc_view_sdk.ready", function()
    {
        var adobeDCView = new AdobeDC.View({clientId: "43b7fe695ddb49899bd5d90f222f5b7c", divId: "adobe-dc-view"});
        adobeDCView.previewFile(
       {
          content:   {location: {url: "local_file.pdf"}},
          metaData: {fileName: "local_file.pdf"}
       }, {embedMode: "IN_LINE", showDownloadPDF: true, showPrintPDF: true});
    });
 </script>

and:

 <script type="text/javascript">
    document.addEventListener("adobe_dc_view_sdk.ready", function()
    {
        var adobeDCView = new AdobeDC.View({clientId: "43b7fe695ddb49899bd5d90f222f5b7c", divId: "adobe-dc-view"});
        adobeDCView.previewFile(
       {
          content:   {location: {url: "/local_file.pdf"}},
          metaData: {fileName: "local_file.pdf"}
       }, {embedMode: "IN_LINE", showDownloadPDF: true, showPrintPDF: true});
    });
 </script>

and:

 <script type="text/javascript">
    document.addEventListener("adobe_dc_view_sdk.ready", function()
    {
        var adobeDCView = new AdobeDC.View({clientId: "43b7fe695ddb49899bd5d90f222f5b7c", divId: "adobe-dc-view"});
        adobeDCView.previewFile(
       {
          content:   {location: {url: "file:///C:/my/sandbox/local_file.pdf"}},
          metaData: {fileName: "local_file.pdf"}
       }, {embedMode: "IN_LINE", showDownloadPDF: true, showPrintPDF: true});
    });
 </script>

but all three don't work.

I always just get a "File preview error":

In the Adobe View SDK repo, I did see the "Work with Local File" example.  But this is not what I'm looking for.  In the example, it uses a File Uploader.  For my purposes, I want to just hardcode a local file location for my PDF into my JS code (preferably relative to my index.html file).  That way I can easily work on my local machine.

Can you please advise?  Thank you!

PS.  Note that my index.html is located in "file:///C:/my/sandbox/" in the same dir as local_file.pdf.