Is it possible to change the column names manually in rhandsontable? Also why cant I add a new row or column here?

## app.R ##
library(shiny)
library(shinydashboard)
library(rhandsontable)
ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(
    
  ),
  dashboardBody(
    rHandsontableOutput('table')
    )
)

server <- function(session,input, output) {
  
  output$table <- renderRHandsontable({
    rhandsontable(iris, width = 550, height = 300) %>%
      hot_context_menu(allowRowEdit = FALSE, allowColEdit = FALSE)
  })
  
 
  
}

shinyApp(ui, server)