R formattable setting row height

Question

I am using formattable and then generating the table and pasting it to a pdf document as an html widget as you can see from the code. However I would like to know if there is any way to change the row height of the table!

library("htmltools")
library("webshot")  
library(formattable)
DF <- data.frame(Ticker=c("", "", "", "IBM", "AAPL", "MSFT"),
                 Name=c("Dow Jones", "S&P 500", "Technology", 
                        "IBM", "Apple", "Microsoft"),
                 Value=accounting(c(15988.08, 1880.33, 50, 
                                    130.00, 97.05, 50.99)),
                 Change=percent(c(-0.0239, -0.0216, 0.021, 
                                  -0.0219, -0.0248, -0.0399)))

################################## FUNCTIONS ##################################
unit.scale = function(x) (x - min(x)) / (max(x) - min(x))
export_formattable <- function(f, file, width = "100%", height = NULL, 
                               background = "white", delay = 0.2)
    {
      w <- as.htmlwidget(f, width = width, height = height)
      path <- html_print(w, background = background, viewer = NULL)
      url <- paste0("file:///", gsub("\\\\", "/", normalizePath(path)))
      webshot(url,
              file = file,
              selector = ".formattable_widget",
              delay = delay)
    }
###############################################################################

FT <- formattable(DF, align =c("l","c","r","c"), list(
  Name=formatter("span", 
                 style = x ~ ifelse(x == "Technology", style(font.weight = "bold"), NA)), #NOT APPLIED when we output to PNG with the function!
  #Value = color_tile("white", "orange"),
  Value = color_bar("orange" , fun = unit.scale
                    ),
  Change = formatter("span", 
                     style = x ~ style(color = ifelse(x < 0 , "red", "green"), "font.size" = "18px"), 
                     x ~ icontext(ifelse(x < 0, "arrow-down", "arrow-up"), x)
                     )),
  table.attr = 'style="font-size: 18px; font-family: Calibri";\"')

FT
#OUTPUT the table in the document as an image!
export_formattable(FT,"/outputpath/FT.png")

As you can see there is quite a gap between the rows, and that is ok in an html document but in a pdf looks odd. I have checked the documentation and the web and there is no straightforward answer to this.

How could I reduce the table height for all rows, even if I wanted to set no space whatsoever and put the row contents colliding "touching" the separating row line.