sankey very small with firefox

I have a simple shiny app with a sankey chart. It works on all browsers, but in Firefox is incredibly small to the point of been unusable. Could it be a recent regression?

Mozilla Firefox ESR 38.4.0 on Centos 7. I've given below a snippet of the code and my sessionInfo() details.
I've tried to use height and width (see below) as a way to avoid the issue with no luck.

```
output$sankey <- renderSankeyNetwork({

networkD3::sankeyNetwork(Links = clink, Nodes = cnodes, Source = "source",
Target = "target", Value = "value", NodeID = "id",
colourScale = JS("d3.scale.category20()") ,
fontSize = 12, nodeWidth = 30, height = 700, width = 500)
})
```

```
sessionInfo()
R version 3.2.2 (2015-08-14)
Platform: x86_64-redhat-linux-gnu (64-bit)
Running under: CentOS Linux 7 (Core)

locale:
[1] LC_CTYPE=en_GB.UTF-8
[2] LC_NUMERIC=C
[3] LC_TIME=en_GB.UTF-8
[4] LC_COLLATE=en_GB.UTF-8
[5] LC_MONETARY=en_GB.UTF-8
[6] LC_MESSAGES=en_GB.UTF-8
[7] LC_PAPER=en_GB.UTF-8
[8] LC_NAME=C
[9] LC_ADDRESS=C
[10] LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_GB.UTF-8
[12] LC_IDENTIFICATION=C

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

other attached packages:
[1] dplyr_0.4.3 networkD3_0.2.7
[3] jsonlite_0.9.19 RColorBrewer_1.1-2
[5] classInt_0.1-23 leaflet_1.0.0
[7] data.table_1.9.6 maptools_0.8-37
[9] rgeos_0.3-15 rgdal_1.1-1
[11] sp_1.2-1 shiny_0.12.2

loaded via a namespace (and not attached):
[1] Rcpp_0.12.2 magrittr_1.5
[3] xtable_1.8-0 lattice_0.20-33
[5] R6_2.1.1 tools_3.2.2
[7] parallel_3.2.2 grid_3.2.2
[9] DBI_0.3.1 e1071_1.6-7
[11] htmltools_0.2.6 class_7.3-13
[13] yaml_2.1.13 assertthat_0.1
[15] digest_0.6.8 htmlwidgets_0.5
[17] mime_0.4 httpuv_1.3.3
[19] foreign_0.8-65 chron_2.3-47
```