I am trying to knit an .Rmd document to pdf in R Studio 1.4.1104 on Linux Ubunutu 20.04. This worked fine then stopped working with no obvious cause and the error message:
! You can't use `\end' in internal vertical mode. \enddocument ...cument/end}\deadcycles \z@ \@@end
I tried Yihui Xie's recommended debugging procedures and the verbose output said no LaTeX packages were missing.
I would be grateful for any advice on what to try next.