title: R shiny: slickROutput disappears when switching tabpanel()
body: <p>I am making a <code>Shiny</code> app with <code>tabPanels</code> embedded in a <code>navbarPage</code>.
  In each <code>tabPanel</code>, I generate a serie of image. When switching from one panel to the other one, the image loaded in one of them disappear.</p>
  <p>I have to &quot;refresh&quot; manually the page to see it again. The problem seems similar than the one posted <a href="https://stackoverflow.com/questions/51380071/keep-plots-and-input-values-when-switching-between-tabs">here</a> but I cannot really subset my <code>tabPanels</code>, even though I gave <code>$id</code> and <code>value</code> to them.</p>
  <p>Here is a reproducible example:</p>
  <pre><code>library(shiny)
  library(shinythemes)
  library(slickR)
  
  ## ui ----
  
  # Image list
  imgs &lt;- list(
      stackoverflow =
          &quot;https://upload.wikimedia.org/wikipedia/fr/9/95/Stack_Overflow_website_logo.png&quot;,
      stackexchange =
          &quot;https://upload.wikimedia.org/wikipedia/commons/6/6f/Stack_Exchange_Logo.png&quot;
  )
  
  ui &lt;- navbarPage(title = div(
      HTML('&lt;span style=&quot;font-size:180%;color:white;font-weight:bold;&quot;&gt; Navbarpage&lt;/span&gt;&lt;/a&gt;'),
      tags$style(style = 'position:absolute; right:42px;'),
      tags$style(HTML(&quot;#panel1{font-size: 25px}&quot;)),
      tags$style(HTML(&quot;#panel2{font-size: 25px}&quot;)),
      tags$style(HTML(&quot;#panel_about{font-size: 25px}&quot;))
  ),
  theme = shinytheme(&quot;flatly&quot;),
  windowTitle = &quot;Navbarpage&quot;,
  id = &quot;navbar&quot;,
  
  ## First tabpanel ----
  tabPanel(h1(id = &quot;panel1&quot;, &quot;Panel 1&quot;), value = 1, fluid = TRUE,
           fluidRow(column(4,
                           selectInput(&quot;img_list&quot;, &quot;Image list&quot;,
                                       choices = imgs,
                                       selected = imgs[1])),
                    column(8,
                           slickROutput(&quot;plot_panel1&quot;))),
  ),
  tabPanel(h1(id = &quot;panel2&quot;, &quot;Panel 2&quot;), value = 2, fluid = TRUE,
           fluidRow(column(4,
                           selectInput(&quot;img_list&quot;, &quot;Image list&quot;,
                                       choices = imgs,
                                       selected = imgs[1])),
                    column(8,
                           slickROutput(&quot;plot_panel2&quot;))),
  )
  ) # closes navbarpage
  
  ## server ----
  server &lt;- function(input, output, session){
  
      observe({
          output$plot_panel1 &lt;- renderSlickR({
              slick1 &lt;- slick_list(slick_div(
                  input$img_list,
                  css = htmltools::css(width = &quot;100%&quot;, margin.left = &quot;auto&quot;,
                                       margin.right = &quot;auto&quot;),
                  type = &quot;img&quot;, links = NULL))
              slickR(slick1)
          })
      })
      
      observe({
          output$plot_panel2 &lt;- renderSlickR({
              slick2 &lt;- slick_list(slick_div(
                  input$img_list,
                  css = htmltools::css(width = &quot;100%&quot;, margin.left = &quot;auto&quot;,
                                       margin.right = &quot;auto&quot;),
                  type = &quot;img&quot;, links = NULL))
              slickR(slick2)
          })
      })
  }
  
  shinyApp(ui, server)
  </code></pre>
  <p>And what it produces:
  <a href="https://i.stack.imgur.com/SpBQH.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SpBQH.gif" alt="enter image description here" /></a></p>