Selectize.js documentation link is broken in selectize article in shiny.rstudio.com

The link for usage documentation of of selectize.js redirects to https://github.com/selectize/selectize.js/blob/master/docs/usage.md but github gives 404 error when you open the link.
I don't know where the new documentation is, just wanted to notify the Posit team.

Link for the mentioned article : Shiny - Using selectize input

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