Unexpected behavior using cbind with edited ggplotGrobs - r

Question

I've been trying to edit some plots created by ggplot2 using the functions provided by the packages grid and gridExtra. I realize that ggplot2 alone can make some really nice multifaceted plots. However, in some instances I like to create individual plots and then combine then together later on. While trying to do just that, I came across some unexpected behavior using cbind() with grid.draw() or grid.arrange() when using a ggplot2 graph that had been edited. Below is the code for an MWE:
#Load libraries
library(ggplot2); library(gridExtra)
#Load data
data(mtcars)
#Ggplot
p = qplot(wt,mpg,data=mtcars,color=cyl)
grob = ggplotGrob(p)
#Bold xlabel
grobEdited = editGrob(grid.force(grob),gPath("xlab","GRID.text"),grep=TRUE,gp=gpar(fontface="bold"))
#Visualize
grid.newpage()
grid.draw(grobEdited)
It worked as expected. Now to illustrate the issue, lets cbind() two of the same edited ggplot2 graphs:
#Cbind example with edited graphs
grid.newpage()
grid.draw(cbind(grobEdited,grobEdited))
It didn't work as expected! Now test cbind() on the unedited graphs:
#Cbind example with grob
grid.newpage()
grid.draw(cbind(grob,grob))
Works as expected. I'm new to gridded figures, so is there something I'm doing wrong?

Answer 1

I'm posting an answer following the comment from #user20650. The easiest workaround is to cbind() the ggplot2 graphs before editing them using the editing functions provided by grid or gridExtra:
#Edit after cbind()
grobEdited = editGrob(grid.force(cbind(grob,grob)),gPath("xlab","GRID.text"),global=TRUE,grep=TRUE,gp=gpar(fontface="bold"))
#Visualize
grid.newpage()
grid.draw(grobEdited)