Five years ago, when I was working at the University of Kent, I wrote up some teaching material (with valuable help by Zoltán Fazekas). The material was publicly available under the name Quantitative Politics with R at qpolr.com. I introduced the material in a post back in 2019.
In short, I have decided not to renew the domain qpolr.com. This is not to say that the material will not be publicly available (you will still be able to find the material on GitHub), only that you will eventually no longer be able to find it on qpolr.com.
The simple reason is that I have not worked on it for a long time now and it would take additional work to maintain the material (e.g., to follow state-of-the-art principles and to make sure that all examples are reproducible). My priority has been to work on my Danish book, Introduktion til R, and I have little to no motivation to bring Quantitative Politics with R up to date.
The material has been used in various tutorials (e.g., here and here), it is part of the awesome Awesome R leaning resources, and it is recommended to students at different levels (e.g. here and here).
It was great seeing the material being used by my students and beyond, but there is so much publicly available material to learn R in 2022 in English, that I believe it is not worth my time working on this project (at least not in its current form). If you do link to qpolr.com, consider now changing those links to better alternatives (or, if no better alternative, the PDF on GitHub).