I’m encountering a formatting issue when attempting to render a quarto document from my shiny application. By employing the same example as the solution to this SO question, I can render my quarto, but it doesn’t have the correct formatting.

quarto rendered from RStudio

quarto rendered from shiny application

shiny application

  # UI -----------------------------------------------------------
  ui = fluidPage(
    textInput("author_name", "Author Name", "John Doe"),
    textInput("report_title", "Report Title", "Quarto From Shiny"),
    radioButtons(
      inputId = "report_file_type",
      label = "Report Type",
      choices = c("HTML" = "html", "PDF" = "pdf")
    ),
    downloadButton("report", "Generate report")
  )
  
  # SERVER --------------------------------------------------------
  server = function(input, output) {
    
    output$report <- downloadHandler(
      filename = function() {
        paste("report", input$report_file_type, sep = ".")
      },
      content = function(file) {
        quarto::quarto_render(
          input = "report_template.qmd",
          output_format = input$report_file_type,
          execute_params = list(
            name = input$author_name,
            report_title = input$report_title
          )
        )
        # copy the quarto generated file to `file` argument.
        generated_file_name <- paste("report_template", input$report_file_type, 
                                     sep = ".")
        file.copy(generated_file_name, file)
      }
    )
  }


# 
shinyApp(ui = ui, server = server)

report_template.qmd

---
title: "Untitled"
format: html
editor: visual
---

## Quarto

Quarto enables you to weave together content and executable code into a finished document. To learn more about Quarto see <https://quarto.org>.

## Running Code

When you click the **Render** button a document will be generated that includes both content and the output of embedded code. You can embed code like this:

```{r}
1 + 1
```

You can add options to executable code like this

```{r}
#| echo: false
2 * 2
```

The `echo: false` option disables the printing of code (only output is displayed).

Session info

R version 4.3.3 (2024-02-29)
Platform: x86_64-redhat-linux-gnu (64-bit)
Running under: Red Hat Enterprise Linux 8.9 (Ootpa)

Matrix products: default
BLAS/LAPACK: /usr/lib64/libopenblaso-r0.3.15.so;  LAPACK version 3.9.0

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8     LC_MONETARY=en_US.UTF-8   
 [6] LC_MESSAGES=en_US.UTF-8    LC_PAPER=en_US.UTF-8       LC_NAME=C                  LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

time zone: Europe/Stockholm
tzcode source: system (glibc)

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] lubridate_1.9.2 forcats_1.0.0   stringr_1.5.0   dplyr_1.1.2     purrr_1.0.1     readr_2.1.4     tidyr_1.3.0     tibble_3.2.1   
 [9] ggplot2_3.4.3   tidyverse_2.0.0 gt_0.10.1       bslib_0.6.2     shiny_1.8.1.1  

loaded via a namespace (and not attached):
 [1] gtable_0.3.0        xfun_0.43           processx_3.8.0      tzdb_0.2.0          vctrs_0.6.2         tools_4.3.3         ps_1.6.0           
 [8] generics_0.1.3      fansi_0.5.0         pkgconfig_2.0.3     readxl_1.4.2        webshot_0.5.3       lifecycle_1.0.3     compiler_4.3.3     
[15] munsell_0.5.0       fontawesome_0.5.1   janitor_2.1.0       snakecase_0.11.0    httpuv_1.6.3        htmltools_0.5.7     sass_0.4.9         
[22] yaml_2.3.8          later_1.3.0         pillar_1.9.0        jquerylib_0.1.4     rsconnect_0.8.29    cachem_1.0.6        mime_0.12          
[29] tidyselect_1.2.0    digest_0.6.28       stringi_1.7.12      quarto_1.4          fastmap_1.1.1       grid_4.3.3          colorspace_2.0-2   
[36] cli_3.6.0           magrittr_2.0.3      utf8_1.2.2          withr_2.4.2         scales_1.2.1        promises_1.2.0.1    timechange_0.2.0   
[43] rmarkdown_2.26      cellranger_1.1.0    rLFO_0.1.08         hms_1.1.3           memoise_2.0.1       evaluate_0.20       knitr_1.46         
[50] rlang_1.1.0         Rcpp_1.0.10         ggVennDiagram_1.5.2 xtable_1.8-4        glue_1.6.2          xml2_1.3.3          rstudioapi_0.14    
[57] jsonlite_1.8.4      R6_2.5.1