if (FALSE) { # rlang::is_interactive()
library(shiny)
shinyApp(
  page_fillable(
    # without `as_fill_carrier()`, the plot won't fill the page because
    # `uiOutput()` is neither a fillable container nor a fill item by default.
    as_fill_carrier(uiOutput("ui"))
  ),
  function(input, output) {
    output$ui <- renderUI({
      div(
        class = "bg-info text-white",
        as_fill_item(),
        "A fill item"
      )
    })
  }
)
}
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