Site with multiple markdown files and shiny

Hi
I use Rstudio to build a website consisting of several Rmarkdown-documents as describedhere. However, if I want to run a shiny application as part of an interactive Rmarkdown, this doesn't seem to work. Here is the code in the "shiny-Rmarkdown file" (all chunks, with opening and closing ```).

---
title: "Hello Prerendered Shiny"
output: html_document
runtime: shiny_prerendered
---
```{r, echo=FALSE}
sliderInput("bins", "Number of bins:", min = 1, max = 50, value = 30)
plotOutput("distPlot")
output$distPlot <- renderPlot({
  x <- faithful[, 2]  # Old Faithful Geyser data
  bins <- seq(min(x), max(x), length.out = input$bins + 1)
  hist(x, breaks = bins, col = 'darkgray', border = 'white')
})

This produces (as part of the site with "build site") the html on left side of the picture instead of (when running the document itself instead of building the site) on the right side of the picture:

Any help would be appreciated

Renger