My problem is best described by this app:

library(shiny)
ui <-shinyUI(fluidPage(
  DT::dataTableOutput("tab"),
  title = "example"
))
server <- function (input, output) {
  m = as.data.frame(round(matrix(rnorm(1000), 50), 5))
  output$tab <- DT::renderDataTable(
    m, extensions = 'FixedColumns',
    options = list(
      scrollX = TRUE,
      fixedColumns = list(leftColumns = 2, rightColumns = 1)
    )
  )
  observeEvent(input$tab_rows_selected,{
    print(input$tab_rows_selected)
  })
}
shinyApp(ui=ui, server=server)

When I fix some columns and use multiselection, a frozen column can be selected as well. I think that expected behaviour would be to disable selection of fixed columns. Even when I select frozen columns it doesn't trigger any action.

Or maybe there is some way to disable that selection for particular columns?