title: Cell coloring in Shiny Rendertable
body: <p>I have a very simple issue.  I am trying to conditionally color certain cells of a <code>shiny</code> <code>renderTable</code>.  For some reason the method below is coloring one cell to the right and pushing the cells in the row over one column as well:</p>
  
  <pre><code>test &lt;- data.frame(test1 = c(1:3), test2 = c(4:6))
  test[test$test1 == 1, "test1"] &lt;- '&lt;td style="background-color:red"&gt;'
  
  library(shiny)
  
  ui &lt;- shinyUI(fluidPage(
     tableOutput("tt")
     )
  )
  
  server &lt;- shinyServer(function(input, output) {
  
     output$tt &lt;- renderTable({
       test
     }, sanitize.text.function = function(x) x)
  })
  
  shinyApp(ui = ui, server = server)
  </code></pre>
  
  <p>Is this a bug?  When I inspected the HTML output I saw it is leaving a blank <code>&lt;td&gt; &lt;/td&gt;</code> cell and creating a new <code>&lt;td style="background-color:red"&gt;</code>.  I Also tried:</p>
  
  <pre><code>test[test$test1 == 1, "test1"] &lt;- '&lt;td bgcolor="#FF0000"&gt;1&lt;/td&gt;'
  </code></pre>
  
  <p>This other styling works:</p>
  
  <pre><code>test[test$test1 == 1, "test1"] &lt;- "&lt;strong&gt;1&lt;/strong&gt;"
  </code></pre>
  
  <p>I am trying to avoid more complex solutions such as:</p>
  
  <p><a href="https://stackoverflow.com/questions/22684162/r-shiny-color-dataframe">R shiny color dataframe</a></p>
  
  <p>Is this too simple to work?  Thank you so much.</p>