R-list RStudio Viewer blank (gray) card [Windows 7]

Using flyer in RStudio creates blank maps in the viewer. Only markers can be seen. The console does not display a warning or error message. When I use shiny it is the same in RStudio viewer, but the map can be seen in the FireFox browser listening to the shiny server.

devtools::install_github("rstudio/leaflet");library(leaflet)
m <- leaflet() %>%
  addTiles() %>%  # Add default OpenStreetMap map tiles
  addMarkers(lng = 174.768, lat = -36.852,
             popup = "The birthplace of R")
m  # Print the map

sessionInfo()

R version 3.2.0 (2015-04-16)
Platform: i386-w64-mingw32/i386 (32-bit)
Running under: Windows 7 (build 7601) Service Pack 1

locale:
[1] LC_COLLATE=German_Germany.1252  LC_CTYPE=German_Germany.1252    LC_MONETARY=German_Germany.1252
[4] LC_NUMERIC=C                    LC_TIME=German_Germany.1252    

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

other attached packages:
 [1] geosphere_1.3-13 maps_2.3-9       WDI_2.4          RJSONIO_1.3-0    rgdal_1.0-4      sp_1.1-1        
 [7] leaflet_1.0.0    shiny_0.12.0     dplyr_0.4.1      readxl_0.1.0     memoise_0.2.1   

loaded via a namespace (and not attached):
 [1] digest_0.6.8     htmltools_0.2.6  R6_2.0.1         curl_0.9         assertthat_0.1   grid_3.2.0      
 [7] bitops_1.0-6     stringr_1.0.0    devtools_1.8.0   httr_0.6.1       httpuv_1.3.2     git2r_0.10.1    
[13] rversions_1.0.1  lattice_0.20-31  mime_0.3         DBI_0.3.1        xml2_0.1.1       rstudioapi_0.3.1
[19] jsonlite_0.9.16  stringi_0.4-1    magrittr_1.5     RCurl_1.95-4.6   yaml_2.1.13      tools_3.2.0     
[25] parallel_3.2.0   htmlwidgets_0.5  xtable_1.7-4     lazyeval_0.1.10  Rcpp_0.11.6     

      

        
        
        
      

    

Brilliant code:

library(shiny)
library(leaflet)

r_colors <- rgb(t(col2rgb(colors()) / 255))
names(r_colors) <- colors()

ui <- fluidPage(leafletOutput("mymap"),
                p(),
                actionButton("recalc", "New points"))

server <- function(input, output, session) {
  points <- eventReactive(input$recalc, {
    cbind(rnorm(40) * 2 + 13, rnorm(40) + 48)
  }, ignoreNULL = FALSE)

  output$mymap <- renderLeaflet({
    leaflet() %>%
      addProviderTiles("Stamen.TonerLite",
                       options = providerTileOptions(noWrap = TRUE)) %>%
      addMarkers(data = points())
  })
}

shinyApp(ui, server)

Listening on http://127.0.0.1:5916