Tab titles with html tag objects are not rendered properly

[wch]

Example:

shinyApp(
  fluidPage(
    tabsetPanel(
      tabPanel(tagList(icon("calendar"), "Calendar"), "content"),
      tabPanel("Summary", "content")
    )
  ),
  function(input, output) {}
)

In Shiny 1.6.0, this is what it looks like:

In the dev version (currently 268c9af):

This was introduced by #3315.