For example, if I wanted to have
selectInput("carDropdown", "Variable:",
c("Cylinders" = "cyl",
"Transmission" = "am",
"Gears" = "gear"))
But I want that dropdown to appear in two separate places in the app (and when the user changes one, the other will automatically update since they are representing the same input$carDropdown variable).
I want to do this because I need to repeat a dropdown across two tabs, but it is a very complicated selectizeInput using reactive elements and I do not want to repeat all the code twice.