title: SelectizeInput does not display all choices on shiny.io
body: <p>I have a shiny app that has a <code>selectizeInput</code> widget which gets its about 26000 choices from a remote database in form of reactive data.
  The use of a remote database and reactivity is to avoid lagging and slowness when loading the choices.
  The issue is that when launched on the desktop locally, it works fine but when uploaded on shinyapps.io the widget does not present to the user all available choices.
  I have played around with the widgets attributes to no avail, for example, setting <strong><code>SERVER =TRUE</code></strong> and so on.
  I have put the code I am using below as well as a link to the data I want loaded to the <code>selectizeInput</code> as choices.</p>
  
  <p><strong>UI part</strong> </p>
  
  <pre><code> library(shiny)
   library(DBI)
   library(RMySQL)
   library(shinydashboard)
   library(shinyjs)
  
   ui &lt;- dashboardPage(  
       skin="yellow",  
     dashboardHeader(   ), 
  
    #sidebar content
     dashboardSidebar(
        sidebarMenu(  
  
            selectInput(
              inputId="selectData",
               label=" ", selected = NULL,
               choices=c( "title" )),      
  
         menuItem("Titles Search", tabName = "Titles", icon = icon("font"))
  
          )
         ),
  
       dashboardBody(
  
           tags$head(
          tags$style(HTML("
                    .content-wrapper {
                    background-color: green !important;
                    }
  
                    .main-header {
                    background-color: red !important;
                    }
  
                    "))
  
          ),
  
     tabItems(      
        tabItem(tabName = "Titles",              
              fluidRow(
                 column(width=3,                        
                      box(                         
                        title=" ",
                         solidHeader=TRUE,
                          collapsible=TRUE,
                       width=NULL,
                       selectizeInput('titles', label = "Search by title", 
                  choices = NULL, options = list(
                         placeholder = 'Type the title', maxOptions = 1000, 
                  maxItems = 100,multiple = F, searchConjunction = 'and')),
                       tags$style(type="text/css",
                                  ".selectize- 
          input::after{visibility:hidden;};"
                       )
  
                     )
                  )
                  )
               )                  
           )   
          )
          )
  </code></pre>
  
  <p><strong>Server part</strong></p>
  
  <pre><code>    library(shiny)
      library(DBI)
      library(RMySQL)
      library(shinydashboard)
      library(shinyjs)
  
  
        shinyServer(function(input, output, session) { 
  
          con &lt;- dbConnect(MySQL(), user='XXXX', 
                   port = 3306, password='XXXXX', 
                   dbname='XXXXXX', 
                   host='XXXXXXXX' )
             query &lt;- function(...) dbGetQuery(con, ...)
            on.exit(dbDisconnect(con), add = TRUE)
  
  
  
  selectedData &lt;- reactiveValues()
  
  observeEvent(input$selectData, {
  
    con &lt;- dbConnect(MySQL(), user='XXXXXX', port = 3306, password='XXXX', dbname='XXXXX', host='XXXXXXX' )
    query &lt;- function(...) dbGetQuery(con, ...)
    on.exit(dbDisconnect(con), add = TRUE)
  
    if (input$selectData == "title") {
      selectedData$titledata &lt;- query("SELECT titles FROM titles ;")
    }
  
    updateSelectizeInput(session, "titles",
                         choices =  as.character(unique(selectedData$titledata$titles)),
                         server = TRUE)
  })
  
    session$onSessionEnded(function() { dbDisconnect(con) })
  
   })
  </code></pre>
  
  <p>What am I doing wrong? Is it a shinyapps.io problem or a coding issue?</p>