Label hangs with flexdashboard

[ghost]

Flexdashboard/d3heatmap: With regular intervals [it does not happen every time you render] the label from a mouse over does not disappear when the mouse is moved somewhere else. The image persists over the different pages in flexdashboard.

`---
title: "Untitled"
output: 
  flexdashboard::flex_dashboard:
  orientation: rows
  vertical_layout: scroll

---

```{r setup, include=FALSE}
library(flexdashboard)
library(d3heatmap)
library(corrgram)  # for baseball dataset

```

First page
========================================================

### Chart A

```{r}
data(mtcars)
d3heatmap(mtcars)
```

Second page
==========================================

Row {data-height=1000}
--------------------------------------

### Larger heatmap

```{r}
data(baseball)
b = subset(baseball, select = Atbat:logSal)
rownames(b) = baseball$Name
d3heatmap(b)

```

Sessioninfo:

> sessionInfo()
R version 3.2.2 (2015-08-14)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 14.04.3 LTS

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8     LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                  LC_ADDRESS=C               LC_TELEPHONE=C             LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

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

other attached packages:
[1] corrgram_1.8        d3heatmap_0.6.1.1   flexdashboard_0.1.0

loaded via a namespace (and not attached):
 [1] Rcpp_0.12.5        whisker_0.3-2      magrittr_1.5       cluster_2.0.4      MASS_7.3-45        colorspace_1.2-6   foreach_1.4.3      caTools_1.17.1    
 [9] tools_3.2.2        grid_3.2.2         seriation_1.2-0    png_0.1-7          KernSmooth_2.23-15 registry_0.3       htmltools_0.3.5    iterators_1.0.8   
[17] gtools_3.5.0       digest_0.6.9       bitops_1.0-6       base64enc_0.1-3    gclus_1.3.1        htmlwidgets_0.6    codetools_0.2-14   dendextend_1.1.8  
[25] rsconnect_0.4.2.2  rmarkdown_0.9.6    TSP_1.1-4          gdata_2.17.0       gplots_3.0.1       jsonlite_0.9.20