Nothing
withMathJax2 <- function(...){
path <- "http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"
tagList(tags$head(singleton(tags$script(src = path, type = "text/javascript"))),
..., tags$script(HTML("MathJax.Hub.Queue([\"Typeset\", MathJax.Hub]);")))
}
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