Xetthecum storymap is hosted on GitHub pages at https://imerss.github.io/xetthecum-storymap/
embedr from https://github.com/mccarthy-m-g/embedr
Installation: embedr is not yet available on CRAN but you can install it from this repository:
if(!"devtools" %in% rownames(installed.packages())) install.packages("devtools")
devtools::install_github("mccarthy-m-g/embedr")