Widget initialization fails when hidden in RMarkdown

[paulklemm]

Potentially related to rstudio/DT#204, timelyportfolio/parcoords#40.

DT and parcoords widgets do not render when they are located in either

1. a hidden {.tabset} or
2. within <details></details>.

Minimal Example

sessionInfo() output

R version 4.0.3 (2020-10-10)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 20.04.1 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.9.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.9.0

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

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

other attached packages:
[1] parcoords_1.0.0 DT_0.16         magrittr_1.5   

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.5             rstudioapi_0.11        servr_0.20            
 [4] knitr_1.30             xtable_1.8-4           R6_2.4.1              
 [7] rlang_0.4.8            fastmap_1.0.1          stringr_1.4.0         
[10] tools_4.0.3            xfun_0.18              xaringan_0.18         
[13] htmltools_0.5.0        crosstalk_1.1.0.1      yaml_2.2.1            
[16] digest_0.6.26          shiny_1.5.0            BiocManager_1.30.10   
[19] later_1.1.0.1          htmlwidgets_1.5.2.9000 promises_1.1.1        
[22] evaluate_0.14          mime_0.9               rmarkdown_2.4         
[25] stringi_1.5.3          compiler_4.0.3         jsonlite_1.7.1        
[28] httpuv_1.5.4           renv_0.12.0    

---
title: "Parcoords and Crosstalk"
output: html_document
---

# {.tabset}

## First Tab

## Second tab

```{r main}
shared_iris <- crosstalk::SharedData$new(iris)
parcoords::parcoords(shared_iris)
```

```{r dt}
DT::datatable(shared_iris)
```

When clicking on Second tab:

Upon resizing the window: