`updateSelectizeInput(options = list(...))` can change the `selected` value

[cpsievert]

A minimal reprex is below. Note how, after the update happens, Option 3 is selected, instead of Option 1.

Seems this isn't an issue when multiple = TRUE

library(shiny)

ui <- bslib::page_fluid(
  selectizeInput("foo", "Foo", choices = c("Option 1", "Option 2", "Option 3"))
)

server <- function(input, output, session) {
  observe({
    updateSelectizeInput(
      inputId = "foo",
      options = list(placeholder = "Select an option")
    )
  })
}

shinyApp(ui, server)

A workaround is to include the currently selected value on update:

updateSelectizeInput(
    inputId = "foo",
    selected = isolate(input$foo),
    options = list(placeholder = "Select an option")
)