exitb <- tabPanel(
tags$button(type = "button", id = "exitqa3d", class = "increment btn btn-default", onclick = "window.close();", HTML("<i class ='fa fa-window-close'></i>"), "Exit", style = "background-color: #2c3e50 ; border: none ;padding: 0px 0px; margin-top: -2px")
)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.