Display or hide shiny widget based on navbar panel

I have the shiny dashboard plus below with a shiny widget in the right sidebar. I would like to know how I could display it only when the tabPanel Plot is selected.

library(shiny)
library(shinydashboardPlus)
shinyApp(
  ui = dashboardPagePlus(
    header = dashboardHeaderPlus(
      enable_rightsidebar = TRUE,
      rightSidebarIcon = "gears"
    ),
    sidebar = dashboardSidebar(),
    body = dashboardBody(
      navbarPage("Navbar!",
                 tabPanel("Plot"

                 ),
                 tabPanel("Summary"
                 ))
    ),
    rightsidebar = rightSidebar(
      background = "dark",
      rightSidebarTabContent(
        id = 1,
        title = "Tab 1",
        icon = "desktop",
        active = TRUE,
        uiOutput("sl")

      )

    ),
    title = "Right Sidebar"
  ),
  server = function(input, output) {
    output$sl<-renderUI({
      sliderInput(
        "obs",
        "Number of observations:",
        min = 0, max = 1000, value = 500
      )
    })


  }
)