Empty Shiny iFrame using Blogdown

Using RStudio, Blogdown, Hugo
Theme: "hugo-sugoi"

I get an empty iframe, trying to embed a Shiny App in a Blogdown post.

title: iframe Test
author: ''
date: '2020-09-11'
slug: iframe-test
categories: []
tags: []
runtime: shiny
output: html_document

Some text  above

<iframe height="800" width="100%" frameborder="no" src="https://antoinesoetewey.shinyapps.io/statistics-201/"> </iframe>

Some text below

Chrome > Inspect Elements > Console: No errors

Chrome > Inspect Elements > Elements


I now realize that RStudio's Viewer can only see local content.
If I "Run Document" and then click "Open in Browser" in the window that appears it works.

Is this the best way from RStudio to view Blogdown posts with Shiny apps embedded in iframes?