blogdown and theme loveit / floating table of contents

I was wondering whether anyone here in the forum has used the 'loveit' theme for his/her blogdown blog.
The theme is quite elegant etc. and also features a floating table of contents. However, when writing a post in rmd (R markdown; and not in markdown) headings are not recognized and the table of content doesn't show up. I was wondering whether anyone has experienced somethings similar and has some advice on how to deal with it.

The theme is here

Many thanks.