R shinyBS modal pop up stopped working and can't make it to work with Shiny Server

I have a simple example below of a shinyBS modal pop up concept upon a user entering the site. This was working fine, and now suddenly stopped working. I have shiny server pro. Not only does the modal not show up, but the datatable is also not rendered. It is as if the server side is not running at all. I get a blank page.

library(shiny)
library(shinyBS)
library(DT)

ui <- fluidPage(
  fluidRow(
    bsModal(
      id = 'startupModal',
      title = h4('IMPORTANT NOTICE. MUST READ AND ACKNOWLEDGE!'),
      trigger = '', size = 'large',
      p('The system you are entering is proprietary ... Do not mess with us!')
      )
    ),
  fluidRow(
    mainPanel(
      DT::dataTableOutput('myData'),
      width = 12
      )
    )
  )

server <- function(input, output, session) {
  toggleModal(session, "startupModal", toggle = "open")
  output$myData <- DT::renderDataTable({
    mtcars %>%
      DT::datatable(
        escape = FALSE, class = 'compact', rownames = '', filter = 'none'
        )
    })
  }

shinyApp(ui, server)

If I comment out the modal UI as follows, the page and the datatable render fine.

library(shiny)
library(shinyBS)
library(DT)

ui <- fluidPage(
#   fluidRow(
#     bsModal(
#       id = 'startupModal',
#       title = h4('IMPORTANT NOTICE. MUST READ AND ACKNOWLEDGE!'),
#       trigger = '', size = 'large',
#       p('The system you are entering is proprietary ... Do not mess with us!')
#       )
#     ),
  fluidRow(
    mainPanel(
      DT::dataTableOutput('myData'),
      width = 12
      )
    )
  )

server <- function(input, output, session) {
  toggleModal(session, "startupModal", toggle = "open")
  output$myData <- DT::renderDataTable({
    mtcars %>%
      DT::datatable(
        escape = FALSE, class = 'compact', rownames = '', filter = 'none'
        )
    })
  }

shinyApp(ui, server)

Here is some more information on packages and R running:

R version 3.4.1 (2017-06-30) -- "Single Candle"
Copyright (C) 2017 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> packageVersion('shiny')
[1] ‘1.4.0’
> packageVersion('shinyBS')
[1] ‘0.61’
> packageVersion('DT')
[1] ‘0.5’

shiny-server --version
Shiny Server Pro v1.5.12.1023
Node.js v10.15.3

I tried this with Chrome (including with pop-ups enabled setting) and also on Microsoft Edge. None of them work.